These are the criteria for choosing an audit:
Right now, these audit questions are selected using the following
criteria:
- Recently asked
- Score between 5 and 15 (inclusive)
- Never locked, migrated, or deleted
- No close votes or downvotes, ever
- (On Stack Overflow) at least 100 views
(taken from Shog's answer)
In his answer, he also discusses the reasons why these conditions are not exactly optimal; they sometimes choose questions that should indeed be closed. Such as this one.
Unfortunately, there's not much you can really do about it other than posting here on meta like you just did. It's just one audit failure; just ignore it and continue as normal.
I have cast the first closevote. It also appears that someone has downvoted it, although that wasn't me.