Once the Big East split, there was nothing on god's green earth that could have prevented Creighton from leaving. None. Nothing. That league is the endgame for every non-football school, and the contract they have is massive. MVC could've been a Top 5 league for 10 straight years and Creighton still would've gone.
The only real mistake over the years was not having the foresight to add Butler to the league. Even if they eventually went to the A-10, then BEast, we would've gotten a few higher-profile years off of them. The preference to always be a 10 team league doomed the league, period. Without openings, Butler was allowed to grow outside of our purview.