He supposedly told Klopp personally that he wanted to stay at Bayern, too. So I don't know if Klopp would be willing to go in for him again if he wasn't willing to come the first time. He's said in the past about not wanting players who aren't committed to the project and only want to come only when we're in the Champions League. I hope not winning the Europa League and failing to qualify for the Champions League isn't what put him off, if that was the case then he won't be coming here, even if he changed his mind.
From what I've read he does seem to want to go back to Dortmund, but the fans really don't seem to want him, and Bayern won't want him to go to them and be a threat, which is why I think they'll sell this window if they don't give him a contract. They won't want him to become a free-agent and be able to go to Dortmund freely. It'd be in their interest to sell him to us, or anywhere outside of Germany.
In any case, as I said, this whole thing isn't dead just yet.