I don't think she'd know. I had a quick word with Romany about what would have been involved in canceling it, and from what little of it didn't go over my head, she didn't break the spell on specific people so much as cancel anything of that nature within a certain radius of the school. If I understand Amanda right, quite a significant radius.

I don't know if Amanda would be able to use her talents now to determine if anyone else was affected, and even if she could, I won't allow it - she's voluntarily put her magic beyond reach until she can handle it better, and I owe it to her to support that decision. If need be, one of the telepaths can scan every brain in the house, or we can fly Romany out here, but I think we can work with the assumption that the list Marie gave us is everyone we need to worry about.