Found a workaround.
When I was transported to arathi Highlands, I abaondoned the quest, which teleports you back to Bastion.
Before I accepted the quest again, I did the following
Game Menu (question mark or escape key) >> Options >> System (at the bottom) >> Network
In the Network menu, there are three options.
Optimize network for speed
Enable IPV6 when available
Advanced Combat logging
uncheck them all
Close out of Options menu and back into the game. [Click X on the top right, or close window]
Accept the quest, “He was my student”
Click on the giant mirror to be transported to the instance.
Good Luck.