This seems like a massive missed opportunity on Larian here. It absolutely makes sense to use him! Or ... you know ... do away with the whole "human brain too tiny" nonsense that requires having a full illithid at all.
Basically they need to throw away the entire end fight and redo it completely along with the entire end storyline. The end fight is total garbage anyway (literally no point in the game to do any of the "gather your allies" quests) since it's not even a fight, it's a rush to get to a portal and then dodge environmental bombs. Absurd is putting it lightly.
If they MUST keep the silliness of "human brain dumb" and require an Illithid, PLEASE give us the option to ask Omeluum! Just makes sense!
