I'm a local. On Friday around 3 p.m. I was passing by and drove around the Officecentre's parking lot out of curiosity. Mainly looking to see how it was set up and if there was more than one way out. I know it's not the same time DS was last seen there, but I'll describe my experience if it helps.
There is a parking lot in front of the building and a parking lot behind. There are only two entrances to the front lot, both of which are off Telegraph. To get to the back lot, there are two roads on either side of the building leading from the front parking lot to the back. When I was there, the front parking lot was pretty much filled up with not a whole lot of parking spots, and the back lot was rather vacant. I'd say about 1/4 of the way full. There were a few people coming and going.
The back parking lot butts up to a church and a residential area. It looked like it might be easy to cut across into the residential area on foot. The building is also on top of a hill of sorts, next to a few other buildings. Down the hill is a partially wooded area that contains the Rouge River.