I think that it has happened before that a coach has been hired by a new school, went there and worked for a short time, recruiting, getting a staff hired etc., and then went back to his old school to coach one final bowl game. I would think that would be a little awkward, but a coach who liked his current players might want to do it. Might be doubly awkward (and might not happen) if the first school also has hired its new coach.
The fact that no one has come out with the Bobby Lutz statement is probably an indication that interviewing and/or negotiating is still ongoing. Wake wants to get as good a coach as possible for the least necessary amount of money. The next coach at Wake wants as good a deal for himself, and his new staff in terms of what is important to him, be it facilities improvements, recruiting budget, "academic exceptions" or anything else. I'm sure Wellman has a dollar range for the new coach. I'm sure any coach out there who has a good job has a minimum requirement for even considering a move. That minimum may be different for different new places. Lots of things to negotiate, so it isn't surprising that it isn't a done deal as yet.