ESOCKETTIMEDOUT occurs when the server receiving the webhook does not respond within 5 seconds. The timeout, unfortunately, is not configurable.
It looks like the server (Google) does handle the request, as the row appears to be incremented in the case where the timeout occurs, it just doesn’t handle it fast enough for the webhook server.
Error 500 usually means that the server (Google) had an internal error. Impossible to say what that might be.
As individual webhook calls are not logged, I don’t have visibility into the inner workings from the cloud side (even with a device ID or webhook ID).