Actually. He's having trouble getting a job right? Why not become a chef? I have no clue how it works or if you need a licence or what not but with his apparent skill I can't imagine it would be difficult.
i dunno how loans work in Japan, but i imagine having the money to buy property and secure food resources is a pretty significant barrier to opening a restaurant.
unless you meant becoming a chef for an already established restaurant, where i imagine it's a bit more important to have a pedigree.
but that's just my imagination, which may or may not coincide with reality
To become a 'chief' at most Japanese places, unless the place you're working at is a lower cost family diner or 'fast'/quick food restaurant it's common for them not to even let you handle a knife until something like 10-15 years later, and until then you're just a bus boy/guy who takes care of the phone, etc. You can check alot of different videos on the topic, but generally you can't become a 'chief' without first the 'experience' in 'years'.
Of course that could've changed by now, I'm not entirely sure.