Sounds like the quick link was exposed after the catch was made and if the critter could get to it, it could have been bitten/chewed on. If it was only finger tight, it is possible that it could have loosened up more during the chewing and struggle by the critter. I say it is possible because I had it happen to me with a beaver trap on a drowning rod that I had only finger tightened the quick link. The water level was dropping so it was possible that the struggle lasted a while. When I checked the set, the trap was not in the bed and the lock was out of site. I pulled the drowner rod and only had a section of chain and an open quick link. I was really kicking myself for being a dummy and not tightening the link with a wrench or pliers.
But since the water was only about 3' to 4' deep at most, I put my waders and tater rake to work and a few minutes later I had the beaver and my MB 750 fished out. Still not sure I would have believed it if I had not had it happen to me. The quick link was not damaged, just open. Threads were fine. And the 750 still had a firm grip on the beavers foot. And it was only a few feet downstream from where the deep end of the drowner rod was. I still think the likelyhood of that happening is pretty slim but not impossible.
Not implying that is what happened in your case but it at least a possibility
I guarantee you that I use a tool to tighten quick links now.
Last edited by QuietButDeadly; 12/27/18 07:16 PM.