The model in teh product folder is just the transient model. There is no released average model.
I suppose it would be possible to export and import all the schematic components from pspice. I think the easiest way would be just to import the TPS54120 into Systemvision, then build the rest of the schematic external components using the native library parts. I looked at that webinar, but it was a little hard to follow as I have never used Systemvision. It looks like you can just unzip the PSPICE files to a local directory and then import them (make sure to change the file attributes to uncheck "read only" first)
Vout (Out_0 and Out_1 or pins 1 and 2) of the TPS54120 is the LDO output. The two pins are common inside the IC.