He says its sheilded from physical and magical attacks iirc, even telepathic reaching out it all seems part of the same magic shield.
It doesn't seem so to me. The true soul tadpoles are in stasis too, but they do not appear to be shielded from the absolute. Only the party is.
Also, the encounter with the goblin priestess indicates that
this shielding might prevent transformation. When she gains a glimpse into the character's mind (if they mind meld), she doesn't immediately rally all the goblins to kill you. Instead she imprisons the character to observe the transformation. But she doesn't wait very long, which means she expects the transformation to happen quickly. And when it doesn't, only then does she try to kill the character.
The goblin priestess isn't very aware of what is really going on. But if the true souls are not shielded from the absolute, and it can mind link to them and control them that way, then those actions make sense.
I dont think there is a direct link to the absolute like you are suggesting otherwise Gut Ragzlin and Minthara would have known what we were and attacked immediately
On that point, I agree. While on the outside Absolute is behaving like any other aggresive cult would, on the inside it behaves just like a Shar cell vs cell: no one knows for sure that this is a Shar agent before you (ofc, unless it is Shadowheart with her circlet and armor).