Step 1. Make a lot of money illegally.Sorry, what? By leading theory you mean your random tinfoil thought? How do you imagien one launders game with sex games on steam lmao.
Step 2. Your little brother makes a game and puts it on Steam.
Step 3. Game does badly on Steam, but on the tax sheet, you write that the game made a lot of money. Most of which was paid to hard-working and talented developers (who are actually your partners in crime).
Step 4. Now when your partners in crime spend their illegally-gotten money, they have an explanation about where they got it - they are hard-working and talented developers whose game made a lot of money!
Something like that, I guess.