If I were the one picking the team members, Wakatsuki and Kuroki are the most obvious choices, assuming they're still on the Kengan side. I'd also pick Muteba, but his mercenary mindset might pose a trouble later on. Not to mention, I have a feeling that Muteba's employer (forgot her name) were one of the turncoats somehow; the other suspects I have in mind are either the Gold Pleasure Group or Under Mount; Yamashita Kenzo seems capable enough to do this.
Anyway, Kazzy the Legendary Businessman...add one more epithet to your portfolio, Kaz.