Webhook target returns 502 - dead letter queue config?

Genesys keeps firing events to our compliance endpoint but the target server throws a 502. The webhook status just flips to failed delivery. We need to dump these into a queue for retrying later. Can’t find a toggle in the API config to enable a dead letter queue. The payload structure is simple.

{
 "event": "routing.queue.member.added",
 "data": { "agentId": "123" }
}