I don’t think Bluff would have done much.
Hmm… does he even have anything besides Xykon’s Moderately Escapable Forcecage(which doesn’t seem to block off the floor) and Magic Missile for that?Having someone use a spell that has a 50% fail rate significantly hampers their combat potential, after all.
…Trio?But yes, I agree with the general idea that, given the circumstances, even if Team Evil winning the war was set in stone actually securing the gate was highly unlikely. The "we'll come back in a few weeks and crush the hobgoblins" idea would have been realistically practical with ambushes from thwe Azurites and no trio of high-level spellcasters sitting on top of the throne.