I believe Pettigrew may be Cult Leader (or whatever Cult member can recruit).I should post resoning for my suspicion. As Draco noted before, he has only posted thrice in this thread, once asking for a status update on page one. This may be so he can easily tell who is available to recruit. Possible, plausible, but I'm not sure if it's likely.

However, I'm not sure how dangerous this Cult is. Is it possible one of them has a night kill power?