A gateway API route is admitted (404 and Rewrite Mismatch)

The route object looks valid and one controller-specific assumption no longer applies. The functional path still exists, but one hidden dependency still assumes the old boundary between shared and isolated resources. A hidden dependency still assumes the old shared-service boundary even though the visible workflow stayed intact. The visible workflow still functions, but one dependency continues to assume the previous shared ownership contract. The happy path still looks intact, but one dependency kept assuming the softer boundary model that existed before the hardening work.

• Identify the primary failure signal in the Admitted Route, Controller-specific Backend Alias scenario.
• Separate visible symptoms from the underlying technical dependency.
• Describe the safest recovery path and the follow-up prevention work.

1. Summarize the current impact and the last known change.
2. Collect direct evidence from logs, runtime state, and configuration before changing anything.
3. Separate immediate recovery from permanent prevention work.

Choose the smallest safe recovery action first, then record the prevention work that reduces repeat incidents.