This could've been avoided by a simple alteration: letting us speak with Orpheus.
It really frustrates me that this isn't an option. Especially when you have Lae'zel with you. By that time you already know a lot of what's going on. And you've spoken to Voss, who will tell you that Orpheus will see sense. He won't attack you because he needs you. I mean, what is he going to do? Fight the netherbrain on his own when he has a mind flayer right there who will do that for him? And surely even our pragmatic Emperor would see sense in that.