Why not just turn the CRAC back on?
> you don’t trust the automation unless there’s a big red-painted, mechanically connected lever you can pull to turn it off
Seems like this is one of those cases where you want to override the automation.
Incidentally, we actually had a fire in the office building I worked in long ago. The HVAC didn't shut down, and smoke started to come out of random vents throughout the building. It was chaos. And yet, plenty of workers wanted to finish and send that email they were working on, commit code and push it to the remote server, etc. What sticks with me most is the one guy, a very senior manager, running around yelling at people to get off their computers and get out of the building, because no job is ever worth your life.
Building fires are no joke. Get the F out.