>Looks like a holdover for human trafficking
There is a possibility of many types of crimes only because everything was covert which is probable cause in itself.
Underground tunnels
Stained Mattresses
Baby's Table
Plastic Bags and Bins
A furnace or oven
Some type of gas containers
People exiting through street ventilation grates
Breaking more walls
Is probable cause to do forensics of further crimes.
Forensics would exonerate too.