In a world where grant funding is extremely limited, yes. Funding agencies are looking for any reason to reject a grant. I think the only reason to not retract

In a world where grant funding is extremely limited, yes. Funding agencies are looking for any reason to reject a grant. I think the only reason to not retract the grant(s) would be the difficulty / practicality of doing so. Nonetheless, this guy's PhD is practically worthless in this country. He will be unemployable and unfundable.