What does Chogall have anything to do with this? He is never shown to die in Draenor before highmaul raid. Remember this whole alternate timeline shit? Please dont bring irrelevant stuff into this.
We do know he is dead, we do not know if he can come back. Illidan came back but he absorbed a demons soul, guldan has not been shown to have done that. Rather he is just empowered by fel to the max a non-demon soul person can be. They can retcon some stuff, but as it stands guldan is dead at the end of nighthold.
Please don't tell me I need to kill Archimonde a third time :P
I did kill him on Mythic, but they have said in the past with tweets that Mythic phases are not always cannon (they may have been deleted at this point). Which is why that tweet caused a stir. That Phase may have been cannon, but the archimonde phase was not is what i implied. If i had a screenie of the tweet id show it, im sure someone has it.