He couldn't get healthy because he wasn't able to work with the team doctors because of the lockout.
A little insight here, he seems unlikely to be cut
Could Chris Cooley be a 'cap casualty?' - NFL Nation Blog - ESPN
That said, when I met with Redskins coach Mike Shanahan in December, he mentioned Cooley's injury as one of the bad turning points for the Redskins in 2011 and spoke of how much he liked being able to "set the perimeter" on offense with two very good tight ends. So my belief is that he'd like to have Cooley back. And even if the Redskins decide $3.8 million is too much and they need him to restructure, Cooley's kind of all-in with the Redskins and likely would be amenable to such an idea if it meant staying with the team he loves.