I looked into the Trello Known Issues Page and could not find anything regarding the Kingbreaker.
My Kingbreaker shows no skin, regardless of which of my available skins i try.
I got it about a week ago and it never showed any modded skin, always the basic wood skin.
The red dot reflex sight is just mangled into the stock iron sights.
Also the magazine is floating in the air (sturdy 7.62 extended mag).
And the player hand is gripping (clipping) the weapon wrong.