diff --git a/.github/workflows/openclaw-release-telegram-qa.yml b/.github/workflows/openclaw-release-telegram-qa.yml
index a515fa6c4384..c64426ceb6d6 100644
--- a/.github/workflows/openclaw-release-telegram-qa.yml
+++ b/.github/workflows/openclaw-release-telegram-qa.yml
@@ -1089,12 +1089,15 @@ jobs:
 
           sudo tee "$preload" >/dev/null <<'PRELOAD'
           import process from "node:process";
+          import { isMainThread } from "node:worker_threads";
 
-          if (process.env.OPENCLAW_QA_SUT_PREENTRY_STOP !== "1") {
-            throw new Error("trusted Telegram SUT preload was not armed");
+          if (isMainThread) {
+            if (process.env.OPENCLAW_QA_SUT_PREENTRY_STOP !== "1") {
+              throw new Error("trusted Telegram SUT preload was not armed");
+            }
+            delete process.env.OPENCLAW_QA_SUT_PREENTRY_STOP;
+            process.kill(process.pid, "SIGSTOP");
           }
-          delete process.env.OPENCLAW_QA_SUT_PREENTRY_STOP;
-          process.kill(process.pid, "SIGSTOP");
           PRELOAD
           sudo chown root:root "$preload"
           sudo chmod 0555 "$preload"
diff --git a/test/scripts/openclaw-release-telegram-qa-workflow.test.ts b/test/scripts/openclaw-release-telegram-qa-workflow.test.ts
index 98f4f08321ae..fe2f1d937171 100644
--- a/test/scripts/openclaw-release-telegram-qa-workflow.test.ts
+++ b/test/scripts/openclaw-release-telegram-qa-workflow.test.ts
@@ -546,6 +546,43 @@ describe("release Telegram QA workflow", () => {
     expect(source).toContain('if [[ "${1:-}" == "--root-terminate-uid" ]]');
   });
 
+  it("arms the boundary preload only in the gateway main thread", () => {
+    const createSutStep = workflowStep(
+      workflowJob("run_telegram"),
+      "Create isolated Telegram SUT identity and launcher",
+    );
+    const preloadSource = createSutStep.run?.match(
+      /<<'PRELOAD'\n([\s\S]*?)\nPRELOAD/u,
+    )?.[1];
+    expect(preloadSource).toBeTruthy();
+
+    const workdir = tempDirs.make("openclaw-telegram-preload-");
+    const preloadPath = join(workdir, "preload.mjs");
+    writeFileSync(preloadPath, preloadSource ?? "");
+    const env = { ...process.env };
+    delete env.OPENCLAW_QA_SUT_PREENTRY_STOP;
+
+    const mainResult = spawnSync(process.execPath, ["--import", preloadPath, "-e", ""], {
+      encoding: "utf8",
+      env,
+    });
+    expect(mainResult.status).not.toBe(0);
+    expect(mainResult.stderr).toContain("trusted Telegram SUT preload was not armed");
+
+    const workerResult = spawnSync(
+      process.execPath,
+      [
+        "-e",
+        `const { Worker } = require("node:worker_threads");\n` +
+          `const worker = new Worker('require("node:worker_threads").parentPort.postMessage("ready")', { eval: true, execArgv: ["--import", ${JSON.stringify(preloadPath)}] });\n` +
+          `worker.once("message", () => process.exit(0));\n` +
+          `worker.once("error", (error) => { console.error(error); process.exit(1); });`,
+      ],
+      { encoding: "utf8", env, killSignal: "SIGKILL", timeout: 5_000 },
+    );
+    expect(workerResult.status, workerResult.stderr).toBe(0);
+  });
+
   it("reports the namespace-entry stage when its supervised child fails", () => {
     const source = readFileSync(WORKFLOW_PATH, "utf8");
     const trapLine = source.match(/^\s+(trap 'exit_status=.*' ERR)$/mu)?.[1];