Okafor should file a grievance with the league. If you are going to refuse to play him, than trade him or waive him. Letting him rot on the bench because you don't want him around, but can't find anyone to trade you what you want is shady business.
Colangelo is definitely shady but Okafor has no grievance. He's getting paid ~5M for the last year of his contract. The Suns aren't playing Bledsoe while they wait for a trade offer they like. Should he file a grievance to?
It is funny to hear the griping now with Colangelo, the basketball guy, in charge. His handling of Noel and Okafor is a nice contrast to Hinkie's handling of MCW.
Players can file grievance through the union. The league then has to respond.
While Okafor would most likely lose a hearing, it would mainly be for lack of proof. But it's obvious Philly is intentionally not playing Okafor simply because they don't want him there, not because he isn't good enough to play. The NBA typically frowns upon that crap, and if Okafor did file a grievance could probably get the league to at least strongly "recommend" Philly do something. It's painfully obvious right now Philly is being unrealistic, and probably also a bit spiteful, to the detriment of Okafor.
Bledsoe is a totally different situation. Bledsoe was the starter before he blasted the team and demanded to be traded. The order of events is key.
As for Colqngelo, well, he's been better than Hinkie in terms of bringing in vets to help the team form an identity. He's helped the team move forward. But Hinkie handled the MCW situation far better than Colangelo did with either Noel or Okafor. Colangelo completely screwed up with both big men, while Hinkie sold MCW at peak value.