If they let Furnari out, Casso will eventually see the outside world.
They probably are waiting for an illness to hit, and then he will be given a release.
Didn't he have pancreatic cancer?
Frank Locascio is supposed to be pretty fucked up but he still hasn't been let out despite his vehement protestations.
Locascio must look at the sentences guys like Sal Avellino and Anthony Baratta got during the same timeframe and feel really hard done by.