FWIW:
Blackhawks autorotate just fine, but there's a recommended entry altitude, and airspeed, that if you aren't within easy reach of makes the entry a bit tough, and all ensuing is a catch up game.
The original question was mostly a display of gross ignorance, given that from a high hover, you can't enter an auto, and you are in a not so nice zone of the HV diagram, particularly if you have a high gross weight.
Military helicopters do autorotate. They have to , it's in the spec.
That's the answer to the question originally posed.