Was doing the Coreway Maintenance Request WQ. Got into the mech and couldn’t figure out how to fly down to the rubble in the coreway that needed to be interacted with, so I flew back to the edge of the hole and got out of the mech to try and get back into it and see if that fixed the control issue. I got on my mount and ran back over to where the mech had respawned and clicked on it to enter as before. This disconnected me instantly. When I logged back in to my character I was high in the air off the coast of Isle of Dorn in a fatigue zone. Fell down into the ocean and was able to mount and get back land before dying though.
I had the same problem with moving down. I saw you message, with no replay and looked on wowhead. It seems you have to hit jump to activate the ability to move up and down. After that it worked like swimming or flying.
My experience with that world quest was different. When I was clicked on the machine to enter it, I got DC’d. when I reentered the game on the same toon, I was at the far end of the map in the ocean dying of fatigue. Blizz please fix this.