Why do you think he would meet with the Heat? Both the Jazz and the Celtics are better teams than the Heat so I don't really get it. I got worried about players that talk to bad teams.
The Heat finished pretty strong and lose no one at all to bring him in since he will just go into Bosh's salary slot. I mean the Heat were 11-30 and finished 30-11 to close at 41-41 and just miss the playoffs. Dragic and Whiteside both compliment Hayward's skill set well (and they can sign Hayward and then bring Waiters back if they want to). The Heat have a bunch of nice young players and are a very young team overall. They have no state income tax. Living in Miami in the winter is way better than Boston or Utah. Riley and Spo are proven winners.
The Heat are real competition for any of the major free agents and can't just be disregarded.
That's where the Brad Stevens factor has to kick in.
Also, won't the Heat have trouble signing Hayward AND keeping Waiters+Johnson in that case. And those two were the main reason Miami even went on that 2nd half run.
Without Bosh, the Heat have approximately 56 million in salaries to Whiteside, Dragic, McRoberts, T. Johnson, Winslow, and Richardson. Adebayo is around 2 million bringing that total to 58 million. If they add in Ellington, McGruder, and White that is 9 million (most of which is from Ellington). So that is 67 million. Waiters cap hold is just 3.477 and J. Johnson's cap hold is just 4.8. So that takes them to just over 75 million. So not quite enough for a max, but they can let Ellington go and they have max room again. So I would expect them to do that. They could keep Ellington and let White or McGruder go and release J. Johnson's cap hold and could also create max cap room that way, but I think that is the lesser option since I imagine they would want to keep J. Johnson if possible. After they sign their max free agent, they can then sign Waiters and Johnson to larger contracts (though they don't have Bird rights so they can't go crazy).