I think BE and Squire are right, Simmons will not report because that would force him to face his teammates, the media and the fans. He has insulted each of them. If he does not have the stones to take outside or foul shots during a game, he definitely will not have the stones to show up at the facility now.
One could hope this would be another cautionary note for the NBA and its decision to let the players run the league. As Zambonir says, Simmons no longer needs the money and that is because of the absurd pay structure in the NBA that hands over huge bags of money to young players before they've really earned it on the court. I get why TPTB think that is a good economic model for the league, but it does force them to look past huge downsides as well. In that, they are like every other sports league and most organizations unfortunately. The almighty dollar rules and any means justify that end i.e. keeping the funds rolling in.