I'm not positive I understood this discussion, but Jeff's answer makes it sound like a question with 2+ answers requires three votes to undelete -- the owner can't undelete with a single vote. I don't quite understand the motivation behind the 2+ answer part, so I might be reading it wrong.
Robert's answer was more explicit:
To answer your question, a user cannot (and should not be able to) undo a democratic, voted action. When it takes three users to vote-to-delete a question, it should take three users to vote-to-un-delete a question. The original author should not have any more power than the one-man-one-vote in this case.
If that's still the case, there appears to be a bug. This question was deleted back in March by three delete votes, and then undeleted yesterday by the owner's single undelete vote. The question already had hundreds of answers at that point