You know, if this topic was posted a few years ago, I would probably just dismiss it as highly speculative rumor. But with everything that has happened over the last year, including over the last few months, this *feels* like it could indeed happen. It fits perfectly with their agenda as of late.
The first thing that came to mind was to inform everyone related to you and close friends who may still be witnesses. Just mention this rumor in passing, but don't make it out like it WILL happen. Word it in a way where it sounds like only a cult would do such a thing - give them time to agree with you. Make them think that the Society would never do such a thing. When the time comes, and if this does turn out to be true, they will be shocked beyond belief. Then ask them if they plan on reaffirming their position with the Society, or if they believe it feels too cultish as you talked about earlier. Make them think about why the Society is doing this.
I'll be watching this thread with interest over the next few months.