Ok, I understand exactly what your saying. However, this is a team sport where the players make millions of dollars. So, say I make 12 million but I really want 15 million. The boss says to me "We can pay you that 15, but we won't be able to afford someone to help us win a championship." If I'm a selfish player, sure I take the larger payout. If I'm a team player I'll take a bit less. Yes, I think 3 million is a bit, especially to football players. As for his rookie contract, IT IS A CONTRACT, play it out. You signed the contract, no one put a gun to your head to sign it. I get sick and tired of these football players sitting out because they feel they are worth more. Absolutely ridicules.
Personally, I'd let him walk. If you can make more, then more power to you. One quick question tho, would NE pay him to play for them?