The U.S. Constitution does not actually require a Supreme Court Justice to be a licensed attorney. Disbarment would have no effect for his work.
It would force facts onto the record. That, in turn, forms the groundwork for future investigations, including and up to charges (against, in all likelihood, folks who paid commissions with the intent of paying a bribe) and impeachment.
Every person who has been nominated to the Court has been an attorney.Of course your point stands, the only qualification for a justice is nomination by POTUS and confirmation by the senate.