Miller is still available for good reasons: age, injury history, salary
It wasn't long ago that he was one of the highest paid TEs in the NFL, so it would be hard to accept a a deal for less than $2m which is what I think would uave to happen in order for us to squeeze him in. He's getting older and has had trouble staying healthy so it's hard to argue that we would get better production from him in the future.
Good guy, but not hard to see why he's currently not on the Hawks or any other team. He'll be able to find a job somewhere if he accepts a cheap deal.