There was reportedly a lot of interest in him around the league and rightly so. But I suspect--given his comments recently--that he had his agent put out that he wanted a starting role and "his" team somewhere. Which probably resulted in where he's at right now.
Have to think the Rams would have been more serious with him otherwise as well. They're better with him on their depth chart. And if it was that, then maybe things will come back around and we'll retain him. Seems unlikely with Brown's offer being matched but never know.