I wouldn't be surprised if the puzzle creator was also the owner or investor vast.ai.

1. Set up GPU renting service that is very good for BTC puzzle solving, and other stuff too like machine learning etc. Requires not much capital to do this. Some servers, software engineers, etc.
2. Start a btc puzzle which you know requires a massive amount of gpu resources, magnitudes of order than whatever you spent on funding the btc puzzles in the first place
3. Find a bunch of hosts with their own gpu rigs/machines they rent out to people trying to solve these crazy puzzles
4. Charge your hosts 25% commission on the fees they earn from renting out their machines on your platform. Remember, you put up no capital at all for all of the hardware, electricity, storage of these very expensive gpu rigs
5. Laugh all the way to the bank for the next several decades or longer

Wish I could have thought of that