I would have thought the question is not are they mineproof, but are they christwigg proof? They both look like they could easily pop out of a wet hand like a bar of soap.
I'd say the ergonomics of compacts are they main point against them for underground use. Tiny buttons, commonly used features hidden in menus, all that sort of stuff.
You can get Nikon F4s for a couple of hundred quid these days and they are built to survive jungles, war zones, deserts etc. And without lens and battery they weigh a mere 4lb.