Posting to confirm that this issue still exists as of today.
I'm not sure why Ekwueid.3079 had a hole on their map, but it was not visible or passable for me. I am here right now - NA server, if it matters. A guildie came to look at it and said they had just done this (and used the hole) several weeks ago - but, now the hole is not there. Either the map has been mistakenly reverted in a recent update to the broken state from before, or different instances of the map can sometimes end up in either state. I'm not sure if meta performance aboveground matters - for the past few days, the meta has not been going well.
Thank you so much for finding and posting a video for this route! I do not have a springer or skyscale, yet, so my only available options were base-mastery glider & raptor. For anyone chasing this achievement and the associated mastery point - who don't have a springer, skyscale, or Schrödinger's hole available - this route is the way to go. The dismount trick can be...tricky, but keep at it and you'll get it!