I would imagine this Hard Drive, even if found, might be about impossible to retrieve information from. Liquids may have poured over it, insects may have damaged it and corrosion may have killed it entirely. I also imagine a significant portion of the people who work at the said landfill have already heard about the potential Billion Dollars lost in the middle of it and may have desperately looked for his Hard Drive, possibly even damaging it in the process.
The situation of searching through landfill for hidden monetary value seems extremely dystopian and I really think after this time and effort it is all right to accept the defeat. He will probably not find it or recover any Bitcoin out of it. And the more he despairs, the more Money it will cost him. At the end of the road, he might lose both his Bitcoin and a LOT of Money out of his pockets. It is definitely not worth it if you ask me.
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He lost his money caused by his own fault. He must accept it.
I really support judge's decision about his broken drive. That's enough to say it will never able to be recovered. It's also good bitcoin's total supply is also decreasing quite a lot.
You honestly sound like you are happy of his suffering only because it provides you an advantage. It is true that lost Bitcoin provide an advantage to everybody else, but I presume he has his right to try his best to achieve what looks like an impossible dream.