Most likely, I think the twist is the identity of the absolute AND the exact why we aren't turning, our purpose.
Squid cosplaying aside, I suspect there's some kind of plot for "get critical mass of people to become infected, controlled by 'officers' that all answer directly to someone trying to become a god(ess)".
How and why the Illithid would buy into helping this I'm not sure, assuming it's not some sort of elder brain pulling the strings.
I'm actually guessing the core plot point will turn out to be the genesis/return of some unknown/forgotten god.
Parroting a bit the Bhaalspawn saga, basically.
Possible, but right now I think BG3 is playing up something which was mostly background for the BG1/2: how much of yourself are you willing to change/sacrifice for power?
