I went through this mission several times, the first time I got stuck in a wall, while searching for the orb in the chests. to solve this I had to log out, which of course I have to restart the whole mission again.
The second bug was when I received the orb and then had to talk to Sayeh, she was there but was attack by the enemies near by, after I finished the enemies off, she disappeared and I was not able to finish the quest again.
I am guessing to finish the quest I will have to restart again, but I lost my patience and did not want to do the mission again from the beginning and stopped.
would appreciate a fix thanks.