If he returns to work on his game and gets selected top 10 instead of late first round then I think staying in college to work on it is the better option don't ya thinkyou had me until this. this is where your argument falls flat because it fails to acknowledge that there is no better place to "work on your game" than the NBA/D-league. so if its your position to come back and work on your game....why not work on your game at the best place to work on your game.
they argument you want to make is....stay one more year, be a kid, its fun, not ready to handle being an adult and the pressure that comes with being an NBA player. or academics is super important. stuff the NBA can't offer.