You might as well delete those 2 pictures of the shaft at the insert. They're useless. Is that square object in the bottom of the but a metal lag bolt head or a square piece of wood in a round hole. In either case it's probably not original unless it's an imported cue. I have seen a square piece of wood like that holding in a piece of rebar as a weight in a cheap import many years ago. That was in an old National imported from Taiwan. Does it rattle when you hit a ball or shake it?