Hunter the Vigil
Your cult, sounds like some of the more cultish hunter compacts.
(Not conspiracies like TFV, but compacts smaller less powerful (no pseudo-magic abilities)).
Hunter is the rulebook all about people who think the supernatural is evil.
So you might like to take a good look at the hunter rulebooks.
What cult members would get out of being considered as a hunter compact,
is access to Tactics.
A good example of a Tactic is moral support (quoted below to give you a feel).
A monster might be able to tear a man’s arm off or bite
through his throat, but the truly terrifying ones are those that can
control his thoughts and feelings. Hunters have long been aware that
many creatures of the World of Darkness can do this sort of thing —
some even cause memory loss by their very presence. The Moral Support
Tactic, hopefully enacted before it becomes an issue, gives a cell
some protection against this kind of attack. The secondary actors
exchange words of encouragement and support, psyching each other up,
as it were. The primary actor then says a few words to the cell:
last-minute advice, reminders about Tactics, or just an admonition to
“kill the bastards.” The cell can then enter a dangerous situation
knowing that the members have each other’s backs
Not so ideal for your use. Worth a glance if you have access to the book still.
Second Sight has a chapter on cults. These are much more focused towards the Cthulu-worshiper end of things though.
These cults do grant super-natural powers.
There is a bit of mundanity in there like the Cult-resources merit.
I figure it is worth a mention for anyone who finds this answer later.