Uh, yea why not? Can you just stop showing up to work tomorrow? Of course you can. Just because he is "under contract" doesn't mean he HAS to show up. If he refused to show up, he breaches his contract. Then he is no longer on the team, he doesn't get paid and most of all he looks like a dumbass.
Keep him, send him to the d-league, and see if any other team is willing to pick up his bad attitude after that
Maybe back off the guy , looks like that tweet was bs http://greenstreet.weei.com/sports/...and-jajuan-johnson-leaning-away-from-houston/