I was helping a friend get this achievement and found a post on reddit about this issue someone posted a video of how to get to it
U have to break out of the map for it and is abit annoying but do able, if u cant do it or dont have a skyscale i parked a character on that spot u can just shoot me a message ingame and i can swap so u can teleport to friend there 🙂
I am on EU servers so if u are on NA i wont be able to help u out unfortunately
With the reddit blackout i cant find the video again.