Finally got to read the chapter. Oh how I love this manga
Seems like Mikoto and Misaki's interactions went almost exactly as someone guessed upon seeing the preview panels
I'm not surprised though, I was already convinced.
I also got the zombie vibe, with the few "sane" personnel getting attacked. Misaki is not a level 5 for nothing.
I don't think Misaki is working with Gensei though, it would not make for an interesting twist to have everyone vs Mikoto. It's far more epic if he has a plan to deal with both of them.
It would be cool if Gensei's aim was to gather battle data on them in order to build the Five Over 3 and 5... Though that's most likely not the case... Gensei is one to think absurdly big, the Five Overs are probably nothing more than toys to him.