Alarm boxes in The Bradbury Building

The alarm boxes that the night watchman turns in the building, and that the mob boss asks his cronies to take care of, are possibly old ADT alarm boxes which need to be activated by turning a key in the alarm box receptacle once an hour. If they are not activated in a specfic order at a specified time, an alarm is sent to the monitoring station at the central alarm office and they in turn notify the police that something is amiss. The watchman activates the alarm later on, which causes the police to be alerted and come to the building. A minor plot twist but one perhaps viewers might have missed. Only an old security guard who remembers that old ADT system would recall this.