He knows what? Tiger almost won the freaking Masters after not having played for 6 months. Are you guys kidding? I doubt this has anything to do with the injury either.
I bet that Tiger feels that he isn't progressing any longer and the two had a falling out.
There have been numerous reports of Tiger talking with other players' swing coaches during practice rounds. Those are probably informal job interviews.
Haney probably just wanted to get out, and save face, before he was shit canned.