It seems like Miami holds the cards rather than Tua. He is the one with previous injuries and high risk going into a season without future guaranteed money. I feel like the more Miami holds out, the better of a terrible deal they will get.
I think Tua holds the cards imo. He has shown he can run McDaniels offense really well, has led the team to the playoffs and is probably the second best FA QB next year. If Miami doesn't extend him then they are looking at the following options;
Mike White - could be a decent and cheap replacement but he is unproven.
Justin Fields - They need an accurate passer in the McDaniels offense, so no.
Russel Wilson - no
Dak - I can't imagine Dallas not re-signing him.
Jordan Love - GB isn't gunna fumble this one.
So that is internal and FA.
Draft - they would need to take dart throws at a rookie and I don't see them being close enough to strike for a top QB or two unless they tank a year
Trade - Not much out there. Maybe an option or two but better than Tua in McDaniels offense?