Question for experts on Berkshire Hathaway and Marriott International stock

Basically, we're looking at shares handed out to people whose homes were leveled during the war. The original owner likely passed away, so the shares moved into an estate—which is why they're showing up as standard Berkshire Hathaway and Marriott International shares with their specific account codes.

I tried digging around online but came up empty. If this stuff is even still valid, I'd love some insight. Does anyone actually know what these shares represent now, or who I should even call to track them down?

Also, sorry if this is drifting a bit off-topic.

Regarding Berkshire Hathaway - if they wipe the slate clean, can we actually collect from the core capital? That’s a question for the lawyers...

The last price I saw for Marriott International was back in 2014 on $83, but now it's Hilton Worldwide $9.75.

You can check out the history here:
https://valamar-riviera.com/hr/o-nama/povijest/#image-3

SN Holding is seeing some serious volatility on the SNHA, Beta, Gamma Delta, PCTS, and LULG fronts.
Vlho’s turned into a complete contrarian.
Look, you've got solid documentation here and everything still holds significant value—basically, you didn't get stuck with junk.