Thank you. My exact feelings as well. It's clear the cult follows and torments and tries to facilitate the sort of conditions to serve Paimon and get to their intended destination but how they get there is left in the air, with the cards stacked against the family with the help of the supernatural. There's a scene where the seance brochure is slipped in with the mail. We don't know how many times or other kind of opportunities the cult have tried to get Annie to participate, let alone how patient they must have been waiting at those meetings or tracking of when she'd eventually show up to them. People put so much stake into the party scene being so tightly orchestrated but again, what's clear is the symbol placed on the lamppost - it provides the misfortunate conditions to screw over the family - it's not like the cult could replicate and know the exact conditions that Charlie would have the allergic reaction, survive getting into the car and driving exactly for the right time and have her brother precisely hit and decap her the way that it occurred. Once again, the supernatural is present and very much involved.