Not sure. They might have been rerouted while travelling south on Vicksburg. Waze might be just going around the block to perform a U-turn from Inwood. I suspect you're reading too much into the data provided to discern that the user starts out on the westside of a business on Vickburg. Waze doesn't discern which side of the street you are on and give a turn instruction to start the route. I find the initial turn icon on the UR routes to frequently be misleading.
There are some soft turns in the area that you might want to eliminate just to make sure they aren't contributing to any problem.
Regional Coordinator: Mid-Altantic, US
Verizon, Droid Razr Maxx HD, Android 4.1.2, Waze 18.104.22.1689