diff --git a/tests/entrypoints/test_omni_diffusion.py b/tests/entrypoints/test_omni_diffusion.py
index 2fbe7a8b42b..6eb149ef1d3 100644
--- a/tests/entrypoints/test_omni_diffusion.py
+++ b/tests/entrypoints/test_omni_diffusion.py
@@ -345,7 +345,7 @@ def _setup_multiprocessing_mocks(monkeypatch: pytest.MonkeyPatch, mocker: Mocker
     fake_process_instance = mocker.MagicMock()
     fake_process_instance.start = mocker.MagicMock()
     fake_process_instance.join = mocker.MagicMock()
-    fake_process_instance.is_alive = mocker.MagicMock(return_value=False)
+    fake_process_instance.is_alive = mocker.MagicMock(return_value=True)
     fake_process_instance.terminate = mocker.MagicMock()
     fake_process_class.return_value = fake_process_instance
 
diff --git a/vllm_omni/entrypoints/omni_stage.py b/vllm_omni/entrypoints/omni_stage.py
index 3fa722b032a..19091034a38 100644
--- a/vllm_omni/entrypoints/omni_stage.py
+++ b/vllm_omni/entrypoints/omni_stage.py
@@ -693,8 +693,14 @@ def try_collect(self) -> dict[str, Any] | None:
         assert self._out_q is not None
         try:
             return self._out_q.get_nowait()
-        except Exception:
-            return None
+        except queue.Empty:
+            pass
+        except Exception as e:
+            logger.error("Unexpected error when collecting OmniStage output queue:", exc_info=e)
+            self.stop_stage_worker()
+            raise
+        if self._proc is not None and not self._proc.is_alive():
+            raise RuntimeError(f"OmniStage Worker process died unexpectedly with exit code {self._proc.exitcode}")
 
     def process_engine_inputs(
         self,