He is surrounded by people because that is his Fort, and he has to stay there to become a Duke. Later on, if you revisit him, he will be in his own room with all traps prepared (mines and flamethrowers on the wall) and his most loyal guards only.
If you did not inform to return the Netherstone before coming up, all the guards will start attacking you. Going into his room is forbidden.
I really want to side with him because I like Lawful Evil character but then Larian did him so dirty.
I think you overlooked my point.
Orin can turn into those most trusted guards, but she can't turn into a Steel Watcher - and I don't think either Orin nor the PC will really care about "something being forbidden". It is emphasized many times that Orin is the second best Unholy Assassin, only second to the Dark Urge, and they are both elite. Gortash only has to stay there for the inauguration, after which point he can operate through political puppets - for being such a cunning politician, he for sure forgot to account for the one thing that he admitted as his weakness. It just simply makes him look like an idiot - and remember that when you start Act3, there is a cutscene where Orin literally walks up to Gortash and has him fooled, posing as a Sergeant, and could have killed him right then and there. Even for the inauguration itself, couldn't he conjure some sort of image? Create a mirror image (something akin to Gale's), and run a perfect script in tandem with the Grand Duke for the inauguration, and then quickly get off the stage.
