This setup is so far off standard practice it's shocking.
Freeflowing does not excuse not having proper auto-closing dampers, triggered by the fire alarms or suppression system.
Automatic power disconnects based on fire suppression system triggering are pretty standard. Most of the systems are fail-safe, meaning if the fire suppression panel loses power or is disconnected from the breakers feeding the room, the breakers trip off.
That there were no automatic shutoffs or easily accessible breakers to disable the generators is shocking. Most NOCs I've visited, there are remote genset controls on one of the walls, often remote transfer switch controls as well. At the very least, on the way out the door someone in the NOC should have pushed the right buttons.
I've never even heard of a commercial datacenter that didn't have fire suppression. Some companies go for preaction systems to reduce the chances of a "everything gets completely fucked by water" systems (gaseous systems are the gold standard, hugely expensive to install compared to water.)
They had wood ceilings!?
In my career in the US, I've been around numerous situations where it was pretty obvious the fire inspector was being paid off or at the very least had an extremely cordial relationship with the building management. My guess is that something similar was happening here.
I don't understand how they managed to have insurance, or get the ISO certifications they claimed they had.