He can't just be turned loose - letting him get away with escape just gives other criminals an incentive to escape and defeats the whole purpose of having low security facilities.
He should be returned to a higher security joint to serve his original sentence, throw the book at him for escape, which he has apparently confessed to, so there should be no issues concerning proof of that offense, sentenced on the new crime of escape, and wait for his parole eligibility like any other prisoner.
edit: and he didn't "rehabilitate" himself - he assumed and lived under a false identity to avoid capture - almost certainly another crime, state and federal, as he was receiving SS benefits. Possibly even a stolen identity. More facts are needed.