Yeah I couldn't see him leaving Montreal either. I think The Leafs plan of coaxing a good GM out of another organization may have to come from an American City. I can't see Gainey leaving Montreal for a team he has no ties to, not to mention the fact that his work in Montreal is just starting to come to life.
Rod Smith just mentioned that The Leafs would try it not that Gainey would ever consider it.
He didn't want the job before because of the meddling from above, and the same people are still in charge. So he's going nowhere. During his sister's speach, she quoted him as saying he was going "down the 401, but in the right direction". That's not Toronto.
When he leaves the GM position, he's going to another job in the organization. I believe he's also a vice-president. So he stays with that job, Carbo moves up to GM.