I know it sucks, but in the meantime have you considered slowing those sync tasks down if the user's "last activity" timestamp is older than a few minutes? You might even be able to make it sync faster for active users with the extra overhead afforded there.
Logins, refreshes, clicks, new things synced, etc... can all update the last activity timestamp.
You're incredible guys. Why wouldn't you reach out to him first? Guy spend two years f with you and now he also have to screen your blog for your email too.
The sad fact that you, a random HN commentor, likely has a better means to contact Google than their official Dev channels, perfectly illustrates the OP's point.
Kudos for assisting, its just frustrating to realize its needed.