Thanks so much! Before breaking camp, I took your advice, FunSteak, and opened a strange rectangular wooden box that is under the seat, and there it was....all busted up. The piece that fell out was linked to the attachment point. So I rigged up some bungee cords in an attempt to prevent damage to the cables, and continue our fall camping trip, until we can get a fix near home..
And thanks John, for that e-mail address; I've sent the photos to them, and asked for a part #, in case it needs replacing. The uTube video shows that links can be clicked into each other, so maybe I have enough good links left to make the apparatus useable. However, when I pull the slide out in, the bungee at the right in the pic barely gets taut, but when I put the slide out out, the bungee at the left cannot push the cable carrier down the hole entirely, leaving about 4 inches popping out.
Are these cable carrier's designed to be pushed down a hole? The video shows them with an axis for the radius moving down the pike, but this slide out setup requires axis for the the radius to be fixed at the hole in the floor.