Honestly it's like how people call anything with wheels a "truck" now, nobody cares about the actual definition anymore as long as it looks close enough.

...and that magnet trick really is the way to go, but what @umab35 said about the neodymium ones is totally on point. I had a cheap harbor freight magnet snap right off the chain when I was sweeping for a lost flashlight, and I ended up having to buy a new magnet too. It sucks losing gear like that, especially when it's a favorite piece of kit like your Hogue. I've been there where you're fighting the bottom time and the current, and every second feels like you're watching your money float away. Glad you got it back though, those 45 minutes of hunting feel like forever when your air is dropping.

Did your buddy's fridge seal look like it melted in some spots?

I read where those hostel walking tours are usually run by locals who know all the hidden spots.

Skiff owner here. Next time try a cup of baking soda mixed with water first. Let it sit for an hour before you scrub. Works way faster than vinegar.