I noticed the ModifierLookAt3D with additional rotation set was causing my bones to scale out of control after a bit of time. Added the following to line 155 of res://addons/TwistedIK2/IK_3D/Twisted_ModifierLookAt3D.cs:
twisted_bone.Transform = new Transform(twisted_bone.Transform.basis.Orthonormalized(), twisted_bone.Transform.origin);