This is comic book villain shit. The story isn't told well anywhere that is covering it, YouTubers aren't always exactly great journalists or incentivized to tell a coherent and concise story. But, it's obvious the Bricks and Minifigs folks are lying about damned near everything at every turn and not engaging in good faith.
So, the facts are hard to follow, but I know for a fact the old guy who lost his collection to a shitty corporation is not the bad guy in the story.
He kind of is. The right thing to do here is go straight to court. All this drama, grandstanding, conspiracist thinking, and stunts are bullshit. Sue. Get the judgment. Collect.
You shouldn't have to sue to have contracts honored by large corporations, and it's entirely reasonable to shame the fuck out of a corporation that responds to a situation like this with "fuck you, sue us if you don't like it".
Dealing with the legal system sucks. There is a sizable amount of money that I would give up to avoid having to deal with it. It's probably well under $200k, but it's far above small claims limits.
Nobody in their right mind goes to court as a first resort, especially for an older person who maybe doesn't have all their wits about them and doesn't have the economic means to bring the kind of legal heat you need against a large corporation.