Nope. Autopilot, like cruise control, relieves you of the burden of driving but not of the responsibility of watch [1]. The Crystal Bay also must have had radar and an alarm should have gone off. Yeah, the Crystal Bay was a drone ship but the Navy is the freaking Navy; moreover they were sailing dark in a crowded sea lane. It's impossible not to fault the crew starting with the captain.

ColRegs Rule 5

  Every vessel shall at all times maintain a proper look-out by sight and hearing as well as by all available means appropriate in the prevailing circumstances and conditions so as to make a full appraisal of the situation and of the risk of collision.

[1] https://www.navcen.uscg.gov/pdf/navrules/navrules.pdf