[X] Ask her why she hates magic so much (Empathy+Charisma)
-[X] "What can I say to you that will make you believe that this isn't malicious, what can I say... I can't say anything that will change your mind because nothing can be convincingly said to you that you won't dismiss out of hand because you believe that I'm either not in control of my own actions or am being manipulated by something, so regardless of if you believe me I'm telling you that I'm in complete control of myself and this power, hell if needs be after all this fairy bullshit is dealt with we can have others verify but until then can you at least stop treating me like I'm sick or ill."
I feel like this gets to the heart of the problem we're having here.
One small note here because Molly does know a little of how Denarians work, it is entirely possible, even common for someone in those sorts of pacts to be in total control at the start of their agreement, the trouble is they do not stay in charge because the Fallen has all the experience of millennia to wear away at the self control and virtue of their host. So the easiest time to get someone to set down a coin is when they have just picked it up. That or something like that may well be what Charity fears.