diff --git a/app/models/dispatch_outbox.py b/app/models/dispatch_outbox.py
index 3716137..d143d15 100644
--- a/app/models/dispatch_outbox.py
+++ b/app/models/dispatch_outbox.py
@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from sqlalchemy import Boolean, CheckConstraint, Column, DateTime, Integer, String, Text, func
+from sqlalchemy import Boolean, CheckConstraint, Column, DateTime, ForeignKey, Integer, String, Text, func
 from sqlalchemy.dialects.postgresql import JSONB, UUID
 
 from app.database import Base
@@ -13,8 +13,21 @@ class DispatchOutbox(Base):
     # Nullable since migration 021: cue-task rows still set execution_id +
     # cue_id; message-task rows (deliver_message / retry_message) leave
     # them NULL and reference message_id in the payload instead.
-    execution_id = Column(UUID(as_uuid=True), nullable=True)
-    cue_id = Column(String(20), nullable=True)
+    # FK declarations match private cueapi: migration 002 declared the
+    # DB-level FKs to executions.id and cues.id with ondelete=CASCADE; the
+    # model previously omitted the FK declaration which was benign drift
+    # (DB constraint still enforced) but broke any future SQLAlchemy ORM
+    # relationship() traversal. Parity port of cueapi/cueapi#594.
+    execution_id = Column(
+        UUID(as_uuid=True),
+        ForeignKey("executions.id", ondelete="CASCADE"),
+        nullable=True,
+    )
+    cue_id = Column(
+        String(20),
+        ForeignKey("cues.id", ondelete="CASCADE"),
+        nullable=True,
+    )
     task_type = Column(String(20), nullable=False, default="deliver")
     payload = Column(JSONB, nullable=False, default={})
     dispatched = Column(Boolean, nullable=False, default=False)
diff --git a/tests/test_qa_observability.py b/tests/test_qa_observability.py
index 6024fba..d63ad6d 100644
--- a/tests/test_qa_observability.py
+++ b/tests/test_qa_observability.py
@@ -9,9 +9,35 @@
 
 from app.models.device_code import DeviceCode
 from app.models.dispatch_outbox import DispatchOutbox
+from app.models.execution import Execution
+from tests.test_poller import _create_due_cue, _create_test_user
 from worker.poller import cleanup_device_codes, cleanup_outbox
 
 
+async def _create_anchor_execution(db_session) -> uuid.UUID:
+    """Create a real User + Cue + Execution and return the execution id.
+
+    Outbox rows have a FK on ``execution_id → executions.id``
+    (ON DELETE CASCADE) per migration 002. Tests that previously
+    inserted outbox rows with synthetic UUIDs relied on the model
+    omitting the FK; now that the model agrees with the migration
+    they must point at a real execution.
+    """
+    user_id = await _create_test_user(db_session)
+    cue = await _create_due_cue(db_session, user_id)
+    exec_id = uuid.uuid4()
+    db_session.add(
+        Execution(
+            id=exec_id,
+            cue_id=cue.id,
+            scheduled_for=datetime.now(timezone.utc),
+            status="pending",
+        )
+    )
+    await db_session.commit()
+    return exec_id
+
+
 # ── Health endpoint ──────────────────────────────────────────────────
 
 
@@ -39,12 +65,15 @@ async def test_health_includes_metrics(client):
 async def test_outbox_cleanup_removes_old_rows(db_session, db_engine):
     """Dispatched outbox rows older than 7 days are deleted."""
     old_time = datetime.now(timezone.utc) - timedelta(days=10)
-    exec_id = uuid.uuid4()
+    exec_id = await _create_anchor_execution(db_session)
 
     await db_session.execute(
         DispatchOutbox.__table__.insert().values(
             execution_id=exec_id,
-            cue_id="cue_old000001",
+            # cue_id NULL — this fixture tests outbox cleanup, not cue
+            # association. Synthetic IDs broke the cues(id) FK once it
+            # was declared on the model (PR #594 second-half drift fix).
+            cue_id=None,
             task_type="deliver",
             payload={},
             dispatched=True,
@@ -67,12 +96,12 @@ async def test_outbox_cleanup_removes_old_rows(db_session, db_engine):
 async def test_outbox_cleanup_keeps_recent(db_session, db_engine):
     """Dispatched outbox rows newer than 7 days are kept."""
     recent_time = datetime.now(timezone.utc) - timedelta(days=1)
-    exec_id = uuid.uuid4()
+    exec_id = await _create_anchor_execution(db_session)
 
     await db_session.execute(
         DispatchOutbox.__table__.insert().values(
             execution_id=exec_id,
-            cue_id="cue_recent0001",
+            cue_id=None,  # see test_outbox_cleanup_removes_old_rows
             task_type="deliver",
             payload={},
             dispatched=True,
@@ -94,12 +123,12 @@ async def test_outbox_cleanup_keeps_recent(db_session, db_engine):
 async def test_outbox_cleanup_keeps_undispatched(db_session, db_engine):
     """Undispatched outbox rows are never cleaned up regardless of age."""
     old_time = datetime.now(timezone.utc) - timedelta(days=30)
-    exec_id = uuid.uuid4()
+    exec_id = await _create_anchor_execution(db_session)
 
     await db_session.execute(
         DispatchOutbox.__table__.insert().values(
             execution_id=exec_id,
-            cue_id="cue_undisp001",
+            cue_id=None,  # see test_outbox_cleanup_removes_old_rows
             task_type="deliver",
             payload={},
             dispatched=False,