Reinhart didn't even sign long term in Florida why would he commit himself to a rebuilding team in Buffalo? Sure if he would have signed a 7 or 8 year deal at <$4M that would have been amazing, but it's completely implausible.
I don't understand why people believe Buffalo refused to sign a willing Reinhart long term. The guy is pretty smart, his moves have been well positioned to maximize his flexibility. He's had 3 chances for long term deals and hasn't taken any of them.
Now he'll be 29 at the start of his next deal and get a team to put down a big number for 7 years. The last two years it'll probably be a contract teams wants off their books, but until then YOLO.
If I'm Reinhart (or his agent) I don't look at the end of the 2017-2018 season and think NOW is the time to sign an 8 year contract with Buffalo. If they ask my number would be high. He knows Eichel is fed up, Kane was traded, and RoR just forced himself off the team; the entire roster is a tire fire.