It depends? One should wonder why no effort was made to suggest he return further east, perhaps to Russia. It is possibly an oversight. But there were other individuals who I think were turned over to Western authorities.

From my time with game modding and cheat development communities, there's some subset that is hyperfocused on money and develops a lack of morals. Some of them eventually get into CC fraud, malware, and other cybercrime for profit. A lot of them never get arrested. At best they're just insufferable assholes, but generally they're not the type of person that is a reliable worker. Basically the same reason you don't want to press a prisoner into military service.

Where do you think the FBI gets its employees?

No way. You don’t let the kitten killers play with other cats.