[@Dead Cruiser] - Absolutely.
To basically put it, Fei has found the mentioned symbol burned into the wall. She's bothered by the entire atmosphere teeming with leftover demonic energy and refuses to go any further in the conjuring room because of it. She has mentioned that she doesn't hear her, the witch, in that her soul-spirit or essence of life is completely snuffed out. Fei can usually see and hear the dead in whichever form. 

I left it open ended with dialogue so that any one else can follow up. I wanted to include a bit of everyone thus Fei addresses everyone in a loose question to possibly trace the symbol's likeness of what have you. Basically anyone can follow up and press further into what it could be. 

Sorry for any misinterpretation.