The ACC is interested in having their tournament at MSG. The article says nothing about MSG being willing or able.
The ACC wants to float this idea, that's fine. Nothing is going to come of it. The new BE would have to fall flat on its face to trigger any escape clause, and that's not going to happen. Not to mention when push comes to shove the Carolina area fans won't want to move the tournament up here because (as we've seen first hand) it'll be a series of Syracuse home games.
Duke, UNC, NC State, and Wake are not going to let that happen.