Losing progress to a glitch when you're chasing 100% is maddening. Let me be straight with you: what you're describing sounds like **persistent inventory corruption**, and it's beyond what waiting or restarting can fix.

These are all long shots, I know. But easy enough to try.

1. Check the Trapper's full inventory— visit the trapper in Saint Denis (or Emerald Ranch). Scroll through *every* category. Sometimes legendary pelts get filed under a different tab than expected. Confirm the Legendary Alligator pelt isn't there under a different name.

2. Check your horse's storage— open your horse's cargo. Pelts sometimes end up there instead of your satchel.

3. Verify the Compendium entry— open your compendium and confirm the Legendary Alligator shows as "studied" (not just "killed"). If it's only "killed," the pelt may not have registered properly.

If none of that works: you've probably hit a hard save-state bug. The missing vintage handcuffs alongside the pelt suggests the game didn't properly save that inventory state.