Outlier detection cascades pod ejection

Your mesh has Envoy outlier detection enabled: a backend host that returns enough 5xx is ejected from the load-balancing pool for a cooldown. At 18:00 one backend pod (of 12) for the catalog service gets briefly slow due to a GC pause and emits some 5xx. Envoy ejects it. But then a SECOND pod, now carrying extra load, also crosses the 5xx threshold and gets ejected; then a third. Within 4 minutes the catalog service's pool has collapsed from 12 healthy hosts to 3, the surviving 3 are overwhelmed, and catalog is effectively down. Dashboards: each individual pod looked momentarily unhealthy, but the underlying cause was transient. No deploy. How do you triage and mitigate?