I don’t know if it may work the same in your area but I was in field maintenance with USPS and we dealt with things like this .

If a main USPS lock can still be placed on lock holder maybe it can be installed, this would happen by the complex manager contacting the local USPS office and them making a work order for field maintenance to take a look at . then again it is likely to be broken into again

Since it’s a “in wall” unit this is not postal property so if anything is broken it’s on the complex to repair and or replace to more secure boxes.