This vista, in the Diessa Plateau, has been bugged on the Fissue of Woe server for at least a week now. The cattlepult event, which allows you to reach the vista, is unable to be performed.
This is because Max Mardine’s assistant, Tigh Snatchskull, just walks aimlessly around the ’pult, instead of getting cows.
Sent a report 5 days ago in game, no response yet, hopefully it gets fixed soon.
Thanks!