Maybe he wouldn't.
That would make sense if he was told not to spend the money. Turning in your boss as the culprit might help your reputation, but it makes for poor job security.
But really, we don't know what happened, or what conversations took place then. What we do know is Dombrowski tried to extend him, but could not get it done. Given that DD was not one to let a budget stand in his way (and still isn't), that strongly suggests Mookie's price to stay was higher than DD was allowed to spend. At that point, Bloom is moot...