Rexouium Tail Bones in rig suddenly break between uploads

I’ve been working with a rexouium avatar for a long while that has long standing been my only and main avatar. I can’t access blender as it isn’t supported on my GPU driver version. Upon version 27 (the 27th revision) of the rexouium, the tail bones (which appear fine in unity, when in the “game” state and in the “editor”) merge to a weird position that is irreversible.
The bones from upload remain that way, I took the Rexouium package and created a fresh unity project in the correct unity version, applied all of the prepackaged contents correctly, and, for the first two times I uploaded the project to VRChat, the bones remained fine. By the third upload, somehow, the tail bones did this. I have no clue how the tail bones manage to fail from one upload to the other, and I’m in dire need for help. Would the tail-bones be incorrectly rigged in Blender, or is a common bug at place?
I’ve had this issue with an older VRChat avatar for a Protogen, after a number of uploads, suddenly, the tail bones irreversibly mangle. I had dynamic bones installed for both, uninstalled them (then, with the tail bones stiff, because of the lack of the dynamic bone script), and still the tail bones were ruined. They appear fine in Unity, only when they upload to VRChat, after a random number of uploads, do they fail. I am asking for any sort of help with this issue, as it has haunted me and costed me hours of work to no avail.
I’m confused on how this could be a rig-issue as dozens of others have uploaded the same Rexouium model to vrchat hundreds of times with and without dynamic bones and this issue has never arisen. Any ideas on what is occuring? The only thing I can speculate to be breaking is an idle-animation controller, the bones on the fbx themselves, or something else. The only thing that I could recount to be an issue is the fact that the bones in the hiearchy have been modified to be facing down rather than straight out. In the VRChat avatar preview (when you select an avatar before you change into it) in the VRChat menu ingame, it appears fine, like it does in unity, but right as I change into it, the avatar’s tail breaks unexplainably.
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