France works for Dak, not the other way around. You don't hire an agent like Todd France unless you want to be at the top of the market pay scale wise. It's like a player who hires Scott Boras in baseball - you know what you are signing up for when you hire him.
Look, Prescott has the right to ask for whatever he wants. Football players have a relatively short shelf life to maximize their earnings, and they should be able to earn whatever they can get someone to pay them, no matter how high that dollar amount is. You can't blame the player for that, or for earning that much if an owner is willing to pay it out.
That being said, an owner also has the right to say no to a request. The Cowboys are not obligated to pay Prescott a market setting contract. They can hold the line and let him leave if they choose. This is how the game works. I think that the concept of the next guy in line becoming the new leader in the clubhouse for QB salaries is a ridiculous method of determining value, but the owners have no one to blame but themselves for this.
Were it my team and my money, I wouldn't pay Prescott that kind of coin. I would be comfortable with letting him leave, but that's me. He's a good football player, but not a market setting type of player.