Locations on the map are incorrect (in my experience) or there are additional locations. Also, the PH is not always a massive tundra yeti. I had this guy spawn near me at around the middle of your PH locations. The next spawn cycle a NORMAL, blue con yeti spawned in that loc.
Also, the northern PH you have on your map should be moved closer to the wall. The massive tundra yeti that spawned the named from that PH is much closer to the edge.