Funny. It has been ages since this event and.. surprise. It really isn't okay irp. But who am I to argue about stuff with you in a faction feedback thread.
EDIT: But well. Guess next time your members could simply talk to the organisers more. Same goes for them. Wait with the event next time, get stuff discussed properly and maybe have a nice three sided (and balanced) event instead of just two sided with a sudden joining side.