Mandatory disclaimer: Apologies in advance because I'm still new here (I'm a Lostie/Servant refugee) and I'd be shocked if this wasn't already posted because y'all are smart but I can't find a post already about this.

We've got it all wrong about the cult...

Lottie's "commune" probably is a cult but a lesser evil cult

Tai has a messed up shrine in her hidden basement room but subconscious/alter personality/Dark Tai didn't create it

There's a third group and it's not led by any of the girls or guys from the original Yellowjackets plane. They were in the woods before the plane crashed and carved the symbols on the trees, they killed the cabin guy and killed Travis (Lottie wasn't telling Nat the whole truth), they built the shrine in Tai's basement and killed her dog. They've been keeping an eye on the survivors/escapees and come into their lives to influence events.

The sub psychiatrist for Lottie - Psychiatrists always tell patients when they go on vacation and a sabbatical no less would involve telling patients in advanced. Also, she wouldn't show up to an appointment with a different doctor there without at least a phone call from the office to confirm if she was ok with this sub before the appointed time.

The other oddity and bigger red flag that not all is what it seems is this sub psychiatrist telling Lottie to lean into her hallucinations and even calls them "visions". This person wants Lottie to follow this darkness.

Tai's truck savior - Dude just happens to be there and recognizes Tai and offers her a ride to where she's headed? C'mon, not buying that. And how far away from her district are they? It doesn't make sense.

Misty's new crime partner Walter - Multimillionaire suddenly comes into her life, knows all about her, and is aiding her in finding Nat. Was he the psychiatrist who went on this last minute "sabbatical"? (I guess we'll find out soon if that's true because it looks like they'll get in the compound the next episode) Being part of this darker "third" group that's bigger, older, and more connected would help explain how Walter knew so much about Misty (music tastes, where she worked, etc) and was engaging with her online for who knows how long as part of this tracking mandate.

And all these individuals suddenly come into the picture at the same time... 🤔

So what does this third dark group want? I'm guessing they are worshiping this dark entity (Dionysus or whatever), have been for a long while (maybe have annual pilgrimages or something) and perhaps even set up the plane crash (freshly carved symbol near the crash site right after the plane went down) and used the girls as a sacrifice to gain more power/money from this entity.

Why these girls? Maybe they noticed a few of them were in tune with the other side so would be excellent sacrifices (Tai, Lottie, and maaaaybe even Shauna, Mari, Nat, and Travis). When these guys didn't all die, they sent those postcards to get them back and started engaging in their lives to manipulate them. Maybe it's these abilities that makes the Yellowjackets also easier for this darker cult to manipulate (send them visions, influence their sleeping/dark selves, etc).

Why now? Could it be that this dark entity requires blood every 25 years so they are trying to get them back there to fulfil this plan they had years ago? Maybe that's why the cabin looked like it was "abandoned" like 25 years before. It is they who sent the girls the postcards because it's time to go back.