Many of the 5 Dk aft cabins, beyond the Car Doors, were transferred into Crew cabins mid/late 90s as they were deemed unsuitable for passengers. They were occupied by Junior Officers & Staff who saw them as a definite step up from the rest of the - as built - Crew cabins. My daughter had one when she travelled back with me from NY after her Gap year at the Masters School in Dobbs Ferry.
They had the facilities and size of Single Passenger Cabins, but were just a bit 'tired', mind you most of 5 Dk was 'a bit tired' in truth!