If you want to retrieve this information on author, it's going to be hard; not because it's actually hard to gather this information, but rather because there might be unforseen cases, which you should consider upfront. And maybe you should re-think your application design.
For example, how to you want to handle the case, that one of your publish instances is down for a moment (e.g. 5 minutes) or for an more extended period of time. Would your approach be able to cope with that situation in a way that you still can reach your business goals?
I would try to avoid that approach and choose a different way.
regards,
Jörg