I find this interesting.
Doujima clearly is the 'boss' of the Alumni this far, what with him being able to intimidate the jackasshole into actually going along with the Shokugeki. (I really wish this had a translated word.) I'm guessing this is part of a test of his own to gauge Megumi's skills.
After all... it's not just a matter of Souma being the best cook around and just having to prove to people that he truly is, like other mangás do. Megumi's weakness is that she's constantly doubting herself and figures she's weak, in part because the years at the middle school section nearly broke her. Even if she hadn't been fired by such a jerkasshole's behavior, she still would have left Tootsuki eventually because she's too vulnerable and would make an innocent mistake.
In fact, that's what happened; she assumed that Souma's cooking skills, which had saved her ass before, would have been enough to help compliment her lesser abilities when she was faced with the rotten vegetables, unaware that it was a trap (Jerkasshole wanted to fire half the class intentionally, as opposed to Inui's more honest treatment). Disrespecting the 'rules' resulted in her firing.
Now, having taken that in mind, if we assume that Doujima is honestly willing to give Megumi a chance because of Souma's guts for challenging an Alumnus (something which never happened before), then he set her up as the leader to make her realize that she can't be weak if she wants to survive at Tootsuki, and she has to earn her own merits. Souma is there to support her, but she can't lean on him too heavily; she must become her own person.
...the only negative point is that there won't be any naked Megumi, I bet. Or even Inui.