The "cultists" are just your run-of-the-mill throwaway alts, as far as i've understood the situation. We've had this exact same problem dozens of times. Only difference, our valuables are now behind private walls. So we just need to sit out the shitstorm and not feed the trolls. Trust me, they get bored fast enough.
Anyway, curious thing happened today. I was contacted by Valcor who alerted me that someone has been building in front of his place. Remembering the yesterday's incident, I thought it's alt griefers fencing him in.
But when I came to the scene, I found someone called Stephanie making a wheat field on Labs' land (you really need to make a fence around it, dude). There was also a herbalist table built there. He did harvest about 3 rows of public wheat and left them unplanted, but he told me he intended to replant it. Either case, I've never seen a griefer behave like this. Plus, this guy claimed he randomly wandered into Bottleneck and decided to settle down here.
Still, I'm a bit suspicious so I didn't grant him citizenship. I did, however, give him permission to settle in the desert, and to use public fields. I think this might be a honest-to-God newb, but we should still keep an eye on him. If he behaves OK for a while, I'll grant him citizenship.