You could put a Nats JetStream connection in line and you'd have a good buffer to catch the notifications. Not fool proof but then you'd need some kind of batch process that looks for any outstanding changes and syncs them.
We do something like this with our systems. External events get written to the event bus but all operations are idempotent on the event bus. So at night we send another round of the days events to clean up any inconsistencies.