diff --git a/src/agents/subagent-announce-delivery.test.ts b/src/agents/subagent-announce-delivery.test.ts
index a562fad21c4..57741517689 100644
--- a/src/agents/subagent-announce-delivery.test.ts
+++ b/src/agents/subagent-announce-delivery.test.ts
@@ -1,8 +1,5 @@
 // Subagent announce delivery tests cover the last-mile routing used when child
 // runs report progress or completion back to the requester session.
-import fs from "node:fs/promises";
-import os from "node:os";
-import path from "node:path";
 import { afterEach, describe, expect, it, vi } from "vitest";
 import { OutboundDeliveryError } from "../infra/outbound/deliver-types.js";
 import {
@@ -4852,183 +4849,3 @@ describe("deliverSubagentAnnouncement completion delivery", () => {
     });
   });
 });
-
-describe("deliverSubagentAnnouncement requester session backfill (issue #86034)", () => {
-  // Regression: image_generate launched from a non-direct-reply turn (heartbeat,
-  // cron, subagent spawn) supplies a completion origin missing `to`. The
-  // already-loaded requester session entry carries `lastTo`/`lastChannel`, so
-  // effectiveDirectOrigin must backfill from it before the deliverability gate,
-  // otherwise generated media is silently dropped.
-  it("backfills to/accountId from the requester session entry when completion origin is incomplete", async () => {
-    const agentId = `backfill-${Date.now()}-${Math.random().toString(16).slice(2)}`;
-    const sessionKey = `agent:${agentId}:telegram:5866004662`;
-    const storeTemplate = path.join(
-      os.tmpdir(),
-      `openclaw-86034-session-${agentId}-{agentId}.json`,
-    );
-    const storePath = storeTemplate.replaceAll("{agentId}", agentId);
-    await fs.writeFile(
-      storePath,
-      JSON.stringify(
-        {
-          [sessionKey]: {
-            sessionId: "telegram-session-1",
-            updatedAt: Date.now(),
-            channel: "telegram",
-            lastChannel: "telegram",
-            lastTo: "5866004662",
-            lastAccountId: "bot-1",
-          },
-        },
-        null,
-        2,
-      ),
-      "utf-8",
-    );
-
-    try {
-      const dispatchGatewayMethodInProcess = createInProcessGatewayMock({
-        result: { payloads: [{ text: "requester voice completion" }] },
-      });
-      testing.setDepsForTest({
-        dispatchGatewayMethodInProcess,
-        getRequesterSessionActivity: () => ({
-          sessionId: "telegram-session-1",
-          isActive: false,
-        }),
-        getRuntimeConfig: () => ({ session: { store: storeTemplate } }) as never,
-      });
-
-      const result = await deliverSubagentAnnouncement({
-        requesterSessionKey: sessionKey,
-        targetRequesterSessionKey: sessionKey,
-        triggerMessage: "image done",
-        steerMessage: "image done",
-        // Origin carries channel but NOT `to` or `accountId` — simulates an
-        // image_generate task created off the direct-reply path.
-        requesterOrigin: { channel: "telegram" },
-        requesterSessionOrigin: { channel: "telegram" },
-        completionDirectOrigin: { channel: "telegram" },
-        directOrigin: { channel: "telegram" },
-        requesterIsSubagent: false,
-        expectsCompletionMessage: true,
-        bestEffortDeliver: true,
-        directIdempotencyKey: "announce-86034-backfill",
-        sourceTool: "image_generate",
-      });
-
-      expectRecordFields(result, {
-        delivered: true,
-        path: "direct",
-      });
-      // The deliverability decision must see the backfilled `to`.
-      expectInProcessAgentParams(dispatchGatewayMethodInProcess, {
-        deliver: true,
-        channel: "telegram",
-        accountId: "bot-1",
-        to: "5866004662",
-      });
-    } finally {
-      await fs.rm(storePath, { force: true });
-    }
-  });
-
-  // Cross-channel safety regression: a stale lastChannel that differs from
-  // the completion origin's channel must not leak its lastTo into the
-  // telegram delivery. mergeDeliveryContext.channelsConflict (delivery-context.shared.ts:233-260)
-  // is the structural guard; this test locks it.
-  it("does not import a cross-channel lastTo when the completion origin's channel differs from lastChannel (cross-channel guard regression)", async () => {
-    const agentId = `xchan-${Date.now()}-${Math.random().toString(16).slice(2)}`;
-    const sessionKey = `agent:${agentId}:telegram:5866004662`;
-    const storeTemplate = path.join(
-      os.tmpdir(),
-      `openclaw-86034-xchan-session-${agentId}-{agentId}.json`,
-    );
-    const storePath = storeTemplate.replaceAll("{agentId}", agentId);
-    await fs.writeFile(
-      storePath,
-      JSON.stringify(
-        {
-          [sessionKey]: {
-            sessionId: "telegram-session-xchan",
-            updatedAt: Date.now(),
-            channel: "telegram",
-            lastChannel: "signal",
-            lastTo: "signal-stale-target",
-            lastAccountId: "signal-bot-1",
-          },
-        },
-        null,
-        2,
-      ),
-      "utf-8",
-    );
-
-    try {
-      const dispatchGatewayMethodInProcess = createInProcessGatewayMock({
-        result: { payloads: [{ text: "requester voice completion" }] },
-      });
-      testing.setDepsForTest({
-        dispatchGatewayMethodInProcess,
-        getRequesterSessionActivity: () => ({
-          sessionId: "telegram-session-xchan",
-          isActive: false,
-        }),
-        getRuntimeConfig: () => ({ session: { store: storeTemplate } }) as never,
-      });
-
-      const result = await deliverSubagentAnnouncement({
-        requesterSessionKey: sessionKey,
-        targetRequesterSessionKey: sessionKey,
-        triggerMessage: "image done",
-        steerMessage: "image done",
-        requesterOrigin: { channel: "telegram", accountId: "telegram-bot-1" },
-        requesterSessionOrigin: { channel: "telegram", accountId: "telegram-bot-1" },
-        completionDirectOrigin: { channel: "telegram", accountId: "telegram-bot-1" },
-        directOrigin: { channel: "telegram", accountId: "telegram-bot-1" },
-        requesterIsSubagent: false,
-        expectsCompletionMessage: true,
-        bestEffortDeliver: true,
-        directIdempotencyKey: "announce-86034-cross-channel",
-        sourceTool: "image_generate",
-      });
-
-      // Structural assertion: the stale signal `to` must not have leaked into
-      // any in-process gateway dispatch, regardless of whether the call ended
-      // up routed (path: "direct") or short-circuited (delivered: false /
-      // path: "none"). The guard is "no cross-channel `to` ever reaches the
-      // gateway", not a specific terminal path.
-      expect(dispatchGatewayMethodInProcess).not.toHaveBeenCalledWith(
-        "agent",
-        expect.objectContaining({ to: "signal-stale-target" }),
-        expect.anything(),
-      );
-      expect(dispatchGatewayMethodInProcess).not.toHaveBeenCalledWith(
-        "agent",
-        expect.objectContaining({ channel: "signal" }),
-        expect.anything(),
-      );
-      for (const call of asMock(dispatchGatewayMethodInProcess).mock.calls) {
-        const params = call[1] as Record<string, unknown> | undefined;
-        if (!params) {
-          continue;
-        }
-        expect(params.to).not.toBe("signal-stale-target");
-        expect(params.channel).not.toBe("signal");
-      }
-
-      // Result-shape assertion: if the dispatcher was invoked at all on the
-      // direct path, it must not have been with the stale signal target.
-      if (
-        (result as { path?: string }).path === "direct" &&
-        (result as { delivered?: boolean }).delivered === true
-      ) {
-        const params = mockCallArg(dispatchGatewayMethodInProcess, 0, 1) as Record<string, unknown>;
-        expect(params.to).not.toBe("signal-stale-target");
-        expect(params.channel).not.toBe("signal");
-      }
-    } finally {
-      await fs.rm(storePath, { force: true });
-    }
-  });
-});
diff --git a/src/agents/subagent-announce-delivery.ts b/src/agents/subagent-announce-delivery.ts
index 169b327f9ce..7af7957cc22 100644
--- a/src/agents/subagent-announce-delivery.ts
+++ b/src/agents/subagent-announce-delivery.ts
@@ -28,11 +28,7 @@ import {
 import { deriveSessionChatTypeFromKey } from "../sessions/session-chat-type-shared.js";
 import { isCronRunSessionKey, isCronSessionKey } from "../sessions/session-key-utils.js";
 import { isNonTerminalAgentRunStatus } from "../shared/agent-run-status.js";
-import {
-  deliveryContextFromSession,
-  mergeDeliveryContext,
-  normalizeDeliveryContext,
-} from "../utils/delivery-context.js";
+import { mergeDeliveryContext, normalizeDeliveryContext } from "../utils/delivery-context.js";
 import {
   INTERNAL_MESSAGE_CHANNEL,
   isDeliverableMessageChannel,
@@ -1228,19 +1224,15 @@ async function sendSubagentAnnounceDirectly(params: {
     const completionDirectOrigin = normalizeDeliveryContext(params.completionDirectOrigin);
     const directOrigin = normalizeDeliveryContext(params.directOrigin);
     const requesterSessionOrigin = normalizeDeliveryContext(params.requesterSessionOrigin);
-    const requesterEntry = loadRequesterSessionEntry(params.targetRequesterSessionKey).entry;
-    // Backfill missing fields (channel, to, accountId) from the requester
-    // session entry's lastChannel/lastTo so a completion origin that carries
-    // a channel but not a `to` (e.g. heartbeat, cron, subagent spawn paths
-    // where `agentTo` is undefined) still resolves an external delivery
-    // target. Without this, every Boolean(channel && to) gate downstream
-    // short-circuits and generated media is silently dropped.
-    const requesterSessionDeliveryFallback = deliveryContextFromSession(requesterEntry);
+    // Merge completionDirectOrigin with directOrigin so that missing fields
+    // (channel, to, accountId) fall back to the originating session's
+    // lastChannel / lastTo. Without this, a completion origin that carries a
+    // channel but not a `to` would prevent external delivery.
     const externalCompletionDirectOrigin =
       stripNonDeliverableChannelForCompletionOrigin(completionDirectOrigin);
     const completionExternalFallbackOrigin = mergeDeliveryContext(
       directOrigin,
-      mergeDeliveryContext(requesterSessionOrigin, requesterSessionDeliveryFallback),
+      requesterSessionOrigin,
     );
     const effectiveDirectOrigin = params.expectsCompletionMessage
       ? mergeDeliveryContext(externalCompletionDirectOrigin, completionExternalFallbackOrigin)
@@ -1248,6 +1240,7 @@ async function sendSubagentAnnounceDirectly(params: {
     const sessionOnlyOrigin = effectiveDirectOrigin?.channel
       ? effectiveDirectOrigin
       : requesterSessionOrigin;
+    const requesterEntry = loadRequesterSessionEntry(params.targetRequesterSessionKey).entry;
     const deliveryTarget = !params.requesterIsSubagent
       ? resolveExternalBestEffortDeliveryTarget({
           channel: effectiveDirectOrigin?.channel,
diff --git a/src/agents/tools/media-generate-background-shared.test.ts b/src/agents/tools/media-generate-background-shared.test.ts
index 32d68aeefba..f5058f8a2da 100644
--- a/src/agents/tools/media-generate-background-shared.test.ts
+++ b/src/agents/tools/media-generate-background-shared.test.ts
@@ -4,12 +4,20 @@ import { beforeEach, describe, expect, it, vi } from "vitest";
 
 const subagentAnnounceDeliveryMocks = vi.hoisted(() => ({
   deliverSubagentAnnouncement: vi.fn(),
+  loadRequesterSessionEntry: vi.fn(() => ({ entry: undefined })),
+}));
+const detachedTaskRuntimeMocks = vi.hoisted(() => ({
+  completeTaskRunByRunId: vi.fn(),
+  createRunningTaskRun: vi.fn(() => ({ taskId: "task-pinned-route" })),
+  failTaskRunByRunId: vi.fn(),
+  recordTaskRunProgressByRunId: vi.fn(),
 }));
 const taskRegistryDeliveryRuntimeMocks = vi.hoisted(() => ({
   sendMessage: vi.fn(),
 }));
 
 vi.mock("../subagent-announce-delivery.js", () => subagentAnnounceDeliveryMocks);
+vi.mock("../../tasks/detached-task-runtime.js", () => detachedTaskRuntimeMocks);
 vi.mock("../../tasks/task-registry-delivery-runtime.js", () => taskRegistryDeliveryRuntimeMocks);
 
 import {
@@ -20,6 +28,9 @@ import {
 
 beforeEach(() => {
   subagentAnnounceDeliveryMocks.deliverSubagentAnnouncement.mockReset();
+  subagentAnnounceDeliveryMocks.loadRequesterSessionEntry.mockReset();
+  subagentAnnounceDeliveryMocks.loadRequesterSessionEntry.mockReturnValue({ entry: undefined });
+  detachedTaskRuntimeMocks.createRunningTaskRun.mockClear();
   taskRegistryDeliveryRuntimeMocks.sendMessage.mockReset();
 });
 
@@ -378,6 +389,65 @@ describe("scheduleMediaGenerationTaskCompletion", () => {
 });
 
 describe("createMediaGenerationTaskLifecycle", () => {
+  it("pins a missing requester target from session state when the task starts", async () => {
+    subagentAnnounceDeliveryMocks.loadRequesterSessionEntry.mockReturnValue({
+      entry: {
+        lastChannel: "telegram",
+        lastTo: "5866004662",
+        lastAccountId: "bot-1",
+      },
+    });
+    subagentAnnounceDeliveryMocks.deliverSubagentAnnouncement.mockResolvedValueOnce({
+      delivered: true,
+    });
+    const lifecycle = createMediaGenerationTaskLifecycle({
+      toolName: "image_generate",
+      taskKind: "image_generation",
+      label: "Image generation",
+      queuedProgressSummary: "Queued image generation",
+      generatedLabel: "image",
+      failureProgressSummary: "Image generation failed",
+      eventSource: "image_generation",
+      announceType: "image generation task",
+      completionLabel: "image",
+    });
+
+    const handle = lifecycle.createTaskRun({
+      sessionKey: "agent:main:telegram:5866004662",
+      requesterOrigin: { channel: "telegram" },
+      prompt: "proof image",
+    });
+    expect(handle?.requesterOrigin).toEqual({
+      channel: "telegram",
+      to: "5866004662",
+      accountId: "bot-1",
+    });
+
+    // Later session drift cannot change the route stored on the task handle.
+    subagentAnnounceDeliveryMocks.loadRequesterSessionEntry.mockReturnValue({
+      entry: {
+        lastChannel: "telegram",
+        lastTo: "other-peer",
+        lastAccountId: "bot-1",
+      },
+    });
+    await lifecycle.wakeTaskCompletion({
+      handle,
+      status: "ok",
+      statusLabel: "completed successfully",
+      result: "generated",
+    });
+    expect(subagentAnnounceDeliveryMocks.deliverSubagentAnnouncement).toHaveBeenCalledWith(
+      expect.objectContaining({
+        completionDirectOrigin: {
+          channel: "telegram",
+          to: "5866004662",
+          accountId: "bot-1",
+        },
+      }),
+    );
+  });
+
   it("returns the completion wake delivery result", async () => {
     subagentAnnounceDeliveryMocks.deliverSubagentAnnouncement.mockResolvedValueOnce({
       delivered: true,
diff --git a/src/agents/tools/media-generate-background-shared.ts b/src/agents/tools/media-generate-background-shared.ts
index 99a80cf7050..3f5a9445d2f 100644
--- a/src/agents/tools/media-generate-background-shared.ts
+++ b/src/agents/tools/media-generate-background-shared.ts
@@ -19,7 +19,12 @@ import {
   resolveRequiredCompletionDeliveryFailureTerminalResult,
   type RequiredCompletionTerminalResult,
 } from "../../tasks/task-completion-contract.js";
-import { normalizeDeliveryContext, type DeliveryContext } from "../../utils/delivery-context.js";
+import {
+  deliveryContextFromSession,
+  mergeDeliveryContext,
+  normalizeDeliveryContext,
+  type DeliveryContext,
+} from "../../utils/delivery-context.js";
 import {
   INTERNAL_MESSAGE_CHANNEL,
   isDeliverableMessageChannel,
@@ -29,7 +34,10 @@ import {
   type AgentGeneratedAttachment,
 } from "../generated-attachments.js";
 import { formatAgentInternalEventsForPrompt, type AgentInternalEvent } from "../internal-events.js";
-import { deliverSubagentAnnouncement } from "../subagent-announce-delivery.js";
+import {
+  deliverSubagentAnnouncement,
+  loadRequesterSessionEntry,
+} from "../subagent-announce-delivery.js";
 import type { SubagentAnnounceDeliveryFailureReason } from "../subagent-announce-dispatch.js";
 
 const log = createSubsystemLogger("agents/tools/media-generate-background-shared");
@@ -141,6 +149,12 @@ function createMediaGenerationTaskRun(params: {
   }
   const runId = `tool:${params.toolName}:${crypto.randomUUID()}`;
   try {
+    // Pin the complete requester route when detached work starts. Completion-time
+    // session state can move to another peer while generation is still running.
+    const requesterOrigin = mergeDeliveryContext(
+      normalizeDeliveryContext(params.requesterOrigin),
+      deliveryContextFromSession(loadRequesterSessionEntry(sessionKey).entry),
+    );
     const task = createRunningTaskRun({
       runtime: "cli",
       taskKind: params.taskKind,
@@ -148,7 +162,7 @@ function createMediaGenerationTaskRun(params: {
       requesterSessionKey: sessionKey,
       ownerKey: sessionKey,
       scopeKind: "session",
-      requesterOrigin: params.requesterOrigin,
+      requesterOrigin,
       childSessionKey: sessionKey,
       runId,
       label: params.label,
@@ -166,7 +180,7 @@ function createMediaGenerationTaskRun(params: {
       taskId: task.taskId,
       runId,
       requesterSessionKey: sessionKey,
-      requesterOrigin: params.requesterOrigin,
+      requesterOrigin,
       taskLabel: params.prompt,
     };
     touchMediaGenerationTaskRunContext(handle);
diff --git a/src/utils/delivery-context.shared.ts b/src/utils/delivery-context.shared.ts
index 8948d7c8f75..a7dcce48f4a 100644
--- a/src/utils/delivery-context.shared.ts
+++ b/src/utils/delivery-context.shared.ts
@@ -243,20 +243,17 @@ export function mergeDeliveryContext(
     normalizedPrimary?.channel &&
     normalizedFallback?.channel &&
     normalizedPrimary.channel !== normalizedFallback.channel;
-  const accountsConflict =
-    normalizedPrimary?.accountId &&
-    normalizedFallback?.accountId &&
-    normalizedPrimary.accountId !== normalizedFallback.accountId;
-  const routesConflict = channelsConflict || accountsConflict;
   return normalizeDeliveryContext({
     channel: normalizedPrimary?.channel ?? normalizedFallback?.channel,
     // Keep route fields paired to their channel; avoid crossing fields between
     // unrelated channels during session context merges.
-    to: routesConflict ? normalizedPrimary?.to : (normalizedPrimary?.to ?? normalizedFallback?.to),
-    accountId: routesConflict
+    to: channelsConflict
+      ? normalizedPrimary?.to
+      : (normalizedPrimary?.to ?? normalizedFallback?.to),
+    accountId: channelsConflict
       ? normalizedPrimary?.accountId
       : (normalizedPrimary?.accountId ?? normalizedFallback?.accountId),
-    threadId: routesConflict
+    threadId: channelsConflict
       ? normalizedPrimary?.threadId
       : (normalizedPrimary?.threadId ?? normalizedFallback?.threadId),
   });
diff --git a/src/utils/delivery-context.test.ts b/src/utils/delivery-context.test.ts
index 8b64b97ab58..bae7a0576e8 100644
--- a/src/utils/delivery-context.test.ts
+++ b/src/utils/delivery-context.test.ts
@@ -53,20 +53,6 @@ describe("delivery context helpers", () => {
     });
   });
 
-  it("does not inherit route fields from a different account on the same channel", () => {
-    const merged = mergeDeliveryContext(
-      { channel: "telegram", accountId: "bot-a" },
-      { channel: "telegram", to: "123", accountId: "bot-b", threadId: "99" },
-    );
-
-    expect(merged).toEqual({
-      channel: "telegram",
-      to: undefined,
-      accountId: "bot-a",
-    });
-    expect(merged?.threadId).toBeUndefined();
-  });
-
   it("uses fallback route fields when fallback has no channel", () => {
     const merged = mergeDeliveryContext(
       { channel: "demo-channel" },