Discuss Divinity Original Sin, as well as comments posted to our Divinity Original Sin Wiki and Divinity Original Sin 2 Wiki
 2
 
I succeeded on my conjurer (high wits/constitution), failed on all other party members.
You need to approch her with a Scholar so you can have dialogue a specific dialogue option first and then choose to help her. Then the fight begin.
I tested this with my entire team and it seems to a hidden Intelligence check. My Mage passed the operation no problem.
if you teleport anything onto gregorius he will aggro and bust the quest. make sure he takes no damage.
There seems to be more than just the Scholar tag neccessary to find the scars. And 17 wits was not enough somehow.
I failed this multiple times on Str and Fin characters and passed it on an Int character. Whether the tweezers dialogue succeeds or not seems to be a hidden Fin check that seems to do nothing.
Fixing her scalp afterwards has a hidden int check. My 10 int character did it successfully with Peace of Mind(fire buff) + Encourage(human buff)
Now I can't stop fighting her, even though she only has 14 HP left. Last time it didn't happen like this.