yes, I have the same issue. I tried to get the achievement 5 time for each of my different characters and even did twice for the same characters and even completed the hole story journal the tower of nightmares and then replay it again to get it and I even join in a group to see if I can get that way, but nothing works. it is bug. I still can't get the achievement for The Nightmare Unveiled (Historical). I hope they will fix it soon.