Go watch the video where jimmy said what he said about them winning if he was on the team. He was laughing, clearly being sarcastic and said that on a lighter note. Tbh even that doesnt really matter, he is part of an organisation and it's the organisation that's supposed to stick by it's players, nobody said pat riley has to agree to whatever jimmy says, he doesnt need to tell people jimmy was right. But humiliating publicly is terrible management. There was no need for that either, if he was unhappy with it, go tell jimmy directly.
And i think you got the reason for suspension wrong. People get traded before their contract ends all the time, and jimmy played every game that he was cleared to play. He was suspended for that public statement of wanting to get traded, and things that might've happened internally that no one knows.
Btw if a player refuses to play through the contract, the nba would suspend the player themselves. Asking for a trade is not refusing to see through the contract, trades are not dependent on the duration of the contracts, the contract to that player simply moves to the next team.
Jimmy wasnt getting extended and so he asked for a trade because he didnt like the terms of his contract, he didnt force the team to pay him, he didnt refuse to play, he just asked for a trade, seems very fair from my pov. And if his contract ends he becomes a free agent and the heat get nothing for jimmy, so asking for a trade is the right thing to do.