Ridgidbody with non-convex meshcollider, Is there any workaround? (Necessary for RaycastHit.textureCoord)

I know non-convex meshcolliders are no longer supported with rididbodys and I know the collision performance would be bad and therefore I don't want to use the meshcollider for collision. I want to use simple colliders for collision but I need a non-convex meshcollider to be able to use RaycastHit.textureCoord.
I planned to put the non-convex meshcollider on a child and deactivate all collisions of the childs layer. That doesn't work.
Because I want to run "RaycastHit.textureCoord" concave colliders from the workshop are no option. Making the ridgidbody kinematic is also not possible for me.
Does anybody know a workaround to use RaycastHit.textureCoord on a ridgidbody?
Ps: I could set the position every fixedUpdate but I hope somebody knows something better then that