"...the Coast Starlight train to Seattle – passed through at about 2:50 a.m. ..."
Amtrak engineers should not be expected to stare at a video screen for their entire shift.
Cameras are employed to see what the train engineers see. They are essential, for example, in determining what the facts of a grade crossing accident are: Were the gates operating and did the vehicle go around them, did the engineer blow the horn, did he apply the brakes, etc.? There is no viewing screen; they simply record to be downloaded later as necessary.