I think this is one of those cases where (you're right) it was really insignificant. But rather than just cooperate with the auditor for, at worst, a minor finding, they decided to fight against oversight and then double down on it.

IMO oversight is important even if the stuff they find is usually trivial. The fact the library system thinks they're beyond oversight is a problem, and I hope the county council deals with that problem. I don't care one bit about what actually happened with this party/event. It's the "cover up" that bothers me.