I read all of the notes and even watched the videos posted in the notes section on this quest and.... they're useful if you already know that it all takes place in Utgarde Catacombs but if you don't then they all suck!
You may inadvertently pick up this quest and for whatever reason while down in the Utgarde Catacombs doing other quests in the area and somehow did not complete this quest at the time you picked it up, if that happened and you are running around later trying to figure out how to complete the quest then these notes are what you are looking for... if not then you have already completed the quest.
Be aware there are lvl 68-69 regular mobs throughout the entire area. Be prepared for that...
#1 This quest is in the Utgarde Catacombs (underground cave area) the cave entrance is /way 56.66 49.57
#2 Go down the swirly cave like entrance, it will open up and start looking like the inside of Utgarde Keep instance. Just keep going straight until you get to /way 57.24 56.22 and turn towards the west direction and go down the first flight of stairs and through the opening into the next room to /way 55.75 57.25
#3 Now if you still have the quest in your quest log for the sake of a possible bugging of the quest just abandon it and retake the quest from the NPC Daegarn. Daegarn is in the cage just on your left.
#4 a. Now when the quest is selected you will notice that it highlights the location of the quest objectives at /way 56 59 which are not correct because that would be through the huge wall and in the mountain side and there is no possible way to get to that location inside of the Utgarde Catacombs. Completely ignore the blue quest objective highlighted minimap area.
b. The fighting ring is right in front of you and the mobs will spawn and then fight you in the general area of /way 55 57.47
#5 After killing two or three of the guys that spawn and fight you in the ring the Ancient Cipher drops on the ground. Pick it up and turn the quest into NPC Glorenfeld located back up the staircase at /way 56.88 53.81
Sumary:
#1 Utgarde Catacombs - Entrance: /way 56.66 49.57
#2 #2 Staircase you go down after you get through main entrance: /way 55.75 57.25
#3 NPC Daegarn (quest giver) location - /way 55.75 57.25
#4 Actual mob spawning location area: /way 55 57.47
#5 After getting item head back up the stairs - Turn in quest to NPC Glorenfeld located at: /way 56.88 53.81