So I have attached my updated macro that I got working after much hassle after updating to SW 2015. The primary thing that concerns me is the fact that I had to add this line:
swPackAndGo.IncludeToolboxComponents = True
But I originally built this macro to take a single drawing/model set of files, and create a copy under a new name. When I run it with the above line set to False (or without it as it was originally not there), the model file doesn't get copied and the new drawing references the original model.