Thanks for all the helpful responses.
Assuming most of these rooms just have large access panels in the wall to pull cables out toward the main Floor?
In the 2 power rooms I mentioned above the walls are concrete block and there is one block missing from the bottom row to pass cables through. I've posted pics from one of the rooms before but I can't find the posts here so I may repost them if they're still on my phone...
2 of the 200A services and 1 of the 400A services are on Union Connector company switches (link below), the others terminate to plain gray steel boxes with Crouse-Hinds E0200 and E0400 panels like the ones linked below, but with double neutrals.
https://www.unionconnector.com/product/company-switch-with-series-16-safecam-receptacles-and-connection-chamber-400-amphttp://www.cooperindustries.com/content/public/en/crouse-hinds/brands/posilok.htmlPosiLok panels have mechanically interlocked connector covers to force proper connection/disconnection order and the connector back shells are keyed in a way that prevents mating with the wrong conductors.
The Union Connector switches have plunger-type Microswitches in the CamLok female connectors. Failure to completely connect all CamLoks will not allow the shunt trip to close and the main breaker cannot be engaged. Because the architects specified double neutrals there is a dummy CamLok for the 2nd neutral. Also these switches have a connection chamber to directly tie in tails or feeder without CamLoks. If the chamber door is opened the shunt trip opens too, de-energizing the switch.