Here's what people will need to understand going forward, so as to not make us all look retarded:

The human traffickers, for the most part, do not have special "human trafficking tunnels". They just repurpose existing tunnels such as this maintainence shaft. I'd imagine it's the same with sewer lines.

They are rats, they go where rats go.

The only positive thing about this misunderstanding I suppose is that it gives the topic a bit more virality, some lore if you will. But we will need to get this correct in the coming years (imo)