1998 w900 n14 cummins. Broken part found in oil pan

I'm doing an overhaul right now due to the #6 cylinder failing (rear one). Which looked like the rings or something failed. Had oil coming through the piston.

So tore everything down. Dropped the oil pan and found a chunk of metal in the pan. It's about 1x1 inch. Nothing else in the pan except that. Picture is attached. Would anyone know what it's from? I can't figure it out

Also, I've attached pictures of #6 piston. Definitely looks like something got jammed up between the cylinder and piston. Scrapped and melted it a bit and there is a ding in the side of it.