C.B.
Since it is a smooth metal ball (and not 2 little magnets that can stick together with intestine between them causing a hole eventually) I would just let him be. Unless you are worried that the size would be difficult or painful to poop out, I think you are done. I have heard of pennies and marbles getting swallowed and those just come out. The penny with the flatness might cause more problems if it got stuck in a bend of the intestine, but a little ball should just roll right through his insides and fall in the toilet. Maybe you will be lucky and hear a little "clink" when it falls in the ceramic bowl, but I would not worry about examining his poop.