Yeah, the loot seems to be randomized.
Which I'm not a fan of, in general, but it wouldn't be as much of a issue if the the "loot table" wasn't so bad.
As I was saying few days ago in the Feedback subforum I would gladly do with fewer of these chests (like, FOUR rather than 20+), but ideally more interesting ones.
Digging out a massive coffer only to find 15 gold coins and pig head doesn't really make much sense. Who did even bother burying this shit?