I don't understand, is it fixable?
I believe what is happening is the Twisted_Skeleton node is out of sync with the Skeleton3D node. The issue only occurs when the skeleton is rotated, correct?
The Twisted_Skeleton3D node needs to rotate as well with the Skeleton3D node, as they must be kept in sync for it to work. If you want to rotate an IK assembly, then you’ll want to rotate a node that is a parent to both the Skeleton3D and the Twisted_Skeleton3D node. I would see if that fixes the issue.