Wasn't it hinted by Mallach and Kasyrra's speech that the only reason they letting Kasyrra do her shtick is so they can steal her soul research? like yeah you're corrupting thousands, armed a crazy cultist like Tollus with a shitton of power, nearly tore reality appart with your science project and summoned Wraiths again and throwing the world into BDMS chaos, BUT!
I wanna see if I can have a soul and still be a God so just note down whatever interesting shit you find before we come in, kill you and steal your research.
At least two of the seven's followers reproduce in such a way that numbers shouldn't matter that much, and even then, their power core is not at risk at the moment, with the kitsunes having weeaboo island and their many colonies and the whoredom all the way down there in sexy Agrabah (which is totally safe for kids, Cait said so)
Lumia does have orcs raiding and pillaging and reproducing constantly and there should be plenty more wasp and bees colonies all around the planet, and also guys like Sanders, which add numbers
So, the thing is, how much of the continent you're trapped in are they willing to burn to get that research?, maybe all of it, but maybe they really believe the champion will do it, so that could be part of their big plan. Let the champion do it, after all, every deity till now likes the champion. Lumia is super nice and believes that you, the champion, can do anything. Keros likes you a lot and in a weird twist, is nicer to you than basically everyone in the tree (how weird is that every kitsune outside of that place is nice to your character and really likes you, even Kiyoko, but as soon as you go there, they revert to be a bunch of assholes?), Mallach seems totally willing to send help at some point and even let you see what afterlife will be for Cait, as a never ending orgy, how nice of him?, and the rest are there I guess... Nareva was into foot stuff which is pretty nice, kudos for that
Point being, till now their whole plan is letting the champion fuck to the extreme (like Kasyrra), and maybe get the champion's soul (like Kasyrra), and kill Tollus at some point because that would be really helpful, like, let me kill that guy please, I'm pretty it will be a good thing. The cult is bound to fall apart without Tollus and magic hands man and the bleached kitsune won't be enough to keep it together, so let me kill Tollus Savin, please let me kill that particular guy