This sounds very difficult, as if any opinion, advice or direction anyone says becomes a target for a rather non-constructive attitude. Nothing to do with you certainly. I think this is something your boss should pick up on, and if asked keep it strictly professional about your relationship with this person and no more. As this person is newly employed I assume there is a probation period before the post is confirmed?

I specialise in asking stupid questions, as after all you are only one question more idiotic than all the other fools!

When you get answers that make no sense I like to take a deep breath, swallow the anger/despair and say that it is not quite clear what they are saying and would they like expand, and let them dig a deeper hole - sooner or later they will get the message.