diff --git a/src/runtime/dispatchers/orchestration.rs b/src/runtime/dispatchers/orchestration.rs
index 99ef7fe..30e1f42 100644
--- a/src/runtime/dispatchers/orchestration.rs
+++ b/src/runtime/dispatchers/orchestration.rs
@@ -974,7 +974,7 @@ impl Runtime {
 
                 // Create a new history manager to append the failure event
                 let mut failure_history_mgr = HistoryManager::from_history(&item.history);
-                failure_history_mgr.append_failed(infra_error.clone());
+                failure_history_mgr.append_failed(&item.instance, item.execution_id, infra_error.clone());
 
                 // Try to commit the failure event
                 let failure_delta = failure_history_mgr.delta().to_vec();
@@ -1356,7 +1356,7 @@ impl Runtime {
             }
         }
 
-        history_mgr.append_failed(error.clone());
+        history_mgr.append_failed(&item.instance, item.execution_id, error.clone());
 
         let metadata = ExecutionMetadata {
             status: Some("Failed".to_string()),
diff --git a/src/runtime/execution.rs b/src/runtime/execution.rs
index c5801c5..1c6d0d0 100644
--- a/src/runtime/execution.rs
+++ b/src/runtime/execution.rs
@@ -273,7 +273,7 @@ impl Runtime {
                 Self::emit_terminal_cancellation_breadcrumbs(history_mgr, instance, execution_id, &outstanding);
 
                 // Add failure event last
-                history_mgr.append_failed(details.clone());
+                history_mgr.append_failed(instance, execution_id, details.clone());
 
                 // Notify parent if this is a sub-orchestration
                 if let Some((parent_instance, parent_id)) = parent_link {
@@ -354,7 +354,7 @@ impl Runtime {
                 Self::emit_terminal_cancellation_breadcrumbs(history_mgr, instance, execution_id, &outstanding);
 
                 // Add failure event last, and propagate cancellation to outstanding sub-orchestrations.
-                history_mgr.append_failed(details.clone());
+                history_mgr.append_failed(instance, execution_id, details.clone());
 
                 for (_schedule_id, child_suffix) in &outstanding.sub_orchestrations {
                     orchestrator_items.push(WorkItem::CancelInstance {
diff --git a/src/runtime/state_helpers.rs b/src/runtime/state_helpers.rs
index 5c4c45c..8359433 100644
--- a/src/runtime/state_helpers.rs
+++ b/src/runtime/state_helpers.rs
@@ -167,14 +167,12 @@ impl HistoryManager {
     }
 
     /// Append an OrchestrationFailed event with the next event_id
-    pub fn append_failed(&mut self, details: crate::ErrorDetails) {
+    pub fn append_failed(&mut self, instance_id: &str, execution_id: u64, details: crate::ErrorDetails) {
         let next_id = self.next_event_id();
-        // Note: instance_id and execution_id should be set from context
-        // For now, use placeholder values as this will be set by the caller
         self.append(Event::with_event_id(
             next_id,
-            "", // instance_id should be set by caller
-            0,  // execution_id should be set by caller
+            instance_id,
+            execution_id,
             None,
             EventKind::OrchestrationFailed { details },
         ));
diff --git a/tests/e2e_samples.rs b/tests/e2e_samples.rs
index d206e24..733eb6e 100644
--- a/tests/e2e_samples.rs
+++ b/tests/e2e_samples.rs
@@ -1360,6 +1360,26 @@ async fn sample_cancellation_parent_cascades_to_children_fs() {
     .await;
     assert!(ok, "timeout waiting for parent cancel failure");
 
+    // Regression: the terminal OrchestrationFailed event must preserve the
+    // instance_id/execution_id so telemetry pipelines reading event payloads
+    // can correlate the cancellation back to the workflow instance.
+    let parent_hist = store.read("inst-sample-cancel").await.unwrap_or_default();
+    let failed = parent_hist
+        .iter()
+        .rev()
+        .find(|e| matches!(&e.kind, EventKind::OrchestrationFailed { .. }))
+        .expect("parent history should contain OrchestrationFailed");
+    assert_eq!(
+        failed.instance_id,
+        "inst-sample-cancel",
+        "OrchestrationFailed must carry the instance_id"
+    );
+    assert_ne!(
+        failed.execution_id,
+        0,
+        "OrchestrationFailed must carry a non-placeholder execution_id"
+    );
+
     // Find child instance (prefix is parent::sub::<id>) and check it was canceled too
     let mgmt = store.as_management_capability().expect("ProviderAdmin required");
     let children: Vec<String> = mgmt