Leaper In The Mists unobtainable?
Same issue here. Gonna try in 30min after the reset.
Update: worked this time, after the daily reset. Just completed a new key and opened the vault.
This glitch will happen with every one of the borderlands JPs. If someone else opens the door, even if you have the key, it will not work for you. If you do it on another character, with the key you already obtained, it should work. It is a bug, but there are ways around it. I have to tell every single one of my guildmates to NOT touch the vault before I do because of this bug.
Just make sure you are the one opening the vault, and it should not bug out on you.
I just had this happen to myself as well. Doing jumping puzzles is very difficult for me (mainly due to vertigo issues), and I had to get a friendly mesmer to help me out. Finally getting both parts of the key and following someone through the door to loot the chest but NO achievement bug… makes me want to cry. I didn’t want the kitten ed chest, I wanted the kitten ed achievement point for the WvW season.
Fail, Anet, fail.