Yes, I meant that if a companion slurps the tadpoles, they just should get changed by Orpheus or Empi.
In my case: if Minthara is my slurper and I have her with me while freeing Orpheus, he should not even ask, just change her, because she is already mostly Illithid.
Astarion and Minthara must subjugate the Brain themselves and become Absolute in that case, they won't behave like Karlach. Making someone forcibly illithid and expecting that character to do what you want afterwards is extremely foolish, it doesn't work that way, I guess Orpheus who is wise enough and has lived for many years should be realizing this and he wouldn't take that risk. He would rather sacrifice himself for his people and the world than create a new Absolute in this way.