I watched him spawn in this spot -- when you enter into the field area from Dranik Scar side, there is a static noc spawn on the left - he spawned just a little further up from that spawn point. I do believe he roams in a circle after spawning.
Dropped the boots in the image I uploaded (sorry, the uploaded image probably should be on the boot item page rather than the named page who drops them) on 9/6/20 on TLP Mangler. He was roaming around the field area outside the halls leading to Dranik's Scar.