Those kids must be the most moronic people in existence (meaning teeneagers) why would they trust that a kingdom that summoned them w/o permission to use as killing machines would ask them any other thing but KILL INDISCRIMINATELY!!! Come on!! Seriously they are gonna have second thoughts after already been briefed on what's essentially is a huge backstabbing operation?
They are clearly in the side inciting war, they can't get away saying that they were manipulated when they have been playing their game all along. Yeah yeah I know the novel might have more info on them but A) I haven't read that and B) This ain't the novel so any argument from that doesn't apply here.