For pandora I unlocked the 100 different names for sand by discovering the slaughterhouse that’s associated with it. That was the last one I had to discover as it was in a odd place. It’s like a destination portal rather than a drop in location, so it makes it easy to miss imo. I would double check with an online guide to make sure each of my discoveries are accounted for or there lack of. For Nekrotafayo it was the first trophy I earned in regards to the location ones. Since it’s the smallest world map-wise I would suggest trying to reestablish footing there

More importantly though, I would suggest using the orbit view then pressing L3 on controller (or it’s keyboard equivalent) and double checking each world section for Pandora and Nekratafayo. This is the cleanest way to ensure you’re not missing any spots. Some places are tied behind Side missions, you may need to double check to make sure the missions have been accepted/completed. Orbit view on the entire planet itself is not useful as some locations are DLC exclusive. This (Pandora in particular) was really tedious to complete. Hope this helped somewhat and best of luck to you if you decide to grind out the plat.