Oh wow, what a bad memory. This exact thing happened in a building I lived in several years ago, a couple of floors above me. It looked like waterfalls outside our windows and water was rushing in under the baseboards. All while every fire alarm in the building was going off and fire truck sirens were blaring outside. Understandably, the fire department would not turn off the water until they had been to every floor to check for fire. On the upside, it's impressive how much water can be delivered by fire sprinklers.

Closer to the topic, the building's management company tried to come after me (a renter) for the expense of the restoration people who were brought in to rip out my drywall and carpet so mold wouldn't form. Maybe they figured tenants were an easier target than the contractor's insurance? Oh, and the management company were the ones who selected and hired the contractors. I had to get very aggressive, with plenty of threats of legal action, to get them to back down. That was fairly easy to do as my state's laws specifically specify liability rules for flooding in multi-tenant buildings. They never did do repairs while I was there - I moved out when my lease expired nearly a year later as they were tying to raise the rent, with drywall still missing.