RigidBody Tail Physics Won't Work

Please someone help me. I’m trying to create a post processing animation and use rigidbody for tail physics. I’ve followed click for click every single guide on YouTube and end up with bones that are flying all over the place and invisible whenever I enable the post process animation. I’ve tried every option within rigidbody function and my physics asset that I can think of over the course of 3 days now but nothing made this work properly. The closest I got was creating a single physics simulated capsule constrainted to the kinematic tail base, and was able to get it to translate side to side after changing 100 options. But when I add a second physics simulated body on the chain, everything turns invisible and grows like crazy. This video I’m posting is me walking you through my process (you can tell I’ve done this a few times by how fast I move).

^hopefully that link works

I have the same problem. I dont know what to do. But people can atleast answer