They usually put LCN informants on military bases to segregate and protect them, but also because they get more freedom than a protected wing at a prison. The food is better too.
I bet that is where Big Joey has been.
As far as sentence reduction, I bet he still serves some time unless he testifies in cases other than Vinny G. He was convicted of 8 murders.
i really believe we will hear from big joey after he shit cans vinny. there gonna use him in any angle they can.