In the opening sequence, when the bus crashes and rolls over on its side, the moment before the bus comes to rest one of the roof emergency exits pops open. Next the inmates punch through the windows to gain freedom.
The fact that it is an armoured bus keeps being mentioned yet all 3 prisoners punched their way through the windows. It is impossible to punch through normal bus glass never mind "armoured" glass.
The United States Navy does not have a brig in New Orleans. The closest brig to New Orleans is the Naval Consolidated Brig, Chesapeake, Virginia.