Veterans

I would be surprised. I mean, it's not like standing guard at an ammunition depot where someone could slip past you if your head was down or your attention distracted.

These guys don't act unless there is an alert from HQ. And there must be a minutes-long sequence of events that has to occur before they would theoretically turn their keys. Plenty of time to get their attention, or wake them up, or something.

They should have some kind of stimulation down in those facilities. Reading, puzzles, training material, etc.