Also I like Knyte idea. And regarding Krzychu's comment, it's not exacly the same as "surrender happens instantly". The difference is, that if your teammate surrender, you can still try to talk to him. While if he rage quit, it's game over.
Ok, what about this situation:
my teammate surrender and leave. my opponents accept surrender. i don't acccept it, just commiting my orders. And make them an offer they can't refuse - vote to end or the game won't proceed:) (they cannot boot me or him, and he won't do his move)