It hangs together very well, and I suspect many of us thought of it as the update happened, but I'm not sure how we could prove it. We could ask about any mental magic effects the sorcerers can detect? They're almost certainly hidden, but it's usually harder to hide things than to detect them when tou're actively searching. Maybe pass it off as worrying about a possible alien ability - they've been here long enough, after all.
...Actually, that's plausible enough they should be checking for it anyway. We only have their word for it that they were trying to kill them, after all.
@PoptartProdigy can we write in a suggestion to check for mental affects?