In truth, the only reason he's not either in a coma, or has left Japan, never to return, is because the Yakuza probably have more important things to worry about than chasing down some ridiculous self-styled **** with a penchant for self-promoting websites.
I'm not an expert on the Yakuza, but when you set up a business in Japan (as I have done), you take it for granted that they'll show up to collect their share. You don't question it, you just smile sweetly, take them to dinner and hand over what they ask for. What you certainly don't do, is question them, let alone "defy" them.