I failed this audit earlier. I marked it as no action needed because as an answer I thought it was okay. I didn't see the question because it said the question was deleted (there was no title or anything). Now that I can see the question that was asked, I think it would still be a valid answer.
That's an interesting case. It had two "not an answer" flags on it (which I personally would have declined), but those flags were automatically marked helpful by the system when the asker deleted their own question, taking the answer with it.
Moderators are usually a little more strict with flags like that for just this reason, that they get used as audit cases. Perhaps answers deleted when the question is removed could be excluded from being used as audits to prevent this.
This is a pretty rare case, though, because I'm not sure I've seen this before.