Stitched strap from a bag or something, detached at that end.
Having been involved in a refueling…and being intimately involved for several years. I'd be really interested in what heated up the primary side water when the rods got pulled if not Uranium. I read all that. I call BS.
Somewhere here someone posted a link to a guy who said, they said it'll hurt you, look I'm fine and …. I can see how he could be convincing. But he was ignorant. I'll look him up if you want. But it's a waste of time.