I'm not sure if you mean that the gate at the north of the Docks map should open up into Winston Avenue (more logical to me) or that the map at the north of the City should...
Anyways, I see the Wayside Docks district encompassing the entire western shore of the City; there may be a similar area on the Eastern shore, but the port sections seem to have been 'gentrified', at least in Dayport.
Don't forget, the portion of the Wayside Docks that we see in Shipping... and Receiving all seem to be part of the same warehouse complex (Rampone Dockside Shipping) - one sealed off from the rest of the district after hours. It's unlikely we'd see any bordello's inside a warehouse complex.
Really, the commentary about "dockside whorekeeps" comes from a snippet of in-game dialogue, and from the 'historical' tendency of such establishments to spring up wherever ships reach port.
Just some idle commentary on your post.