As part of the storyline, I think it might actually work in their favor. They already season 3 is going to less viewers than the past two seasons, so news of Vickie firing her diva, one that many wanted to see, might increase their viewers. It make those who were reluctant to watch as I am, be more interested in it.
In real life Vickie couldn't fire her rookie since she doesn't have the power to do it.