Inspect the scroll (1st floor on top of the safe: ( 23, 0, 6 ) /waypoint 23, 0, 6)
Leave the zone the way you came in - remember the exit is found by using the climbable walls positioned on either side of the southern wall on the 2nd floor. You now need to find and retrieve 3 banner keys. They are not inventory items so your quest will auto-update.
Second walk near a skeleton at ( -997, -96, -1200 ) /waypoint -997, -96, -1200 in The Sinking Sands. A soloable group of 3 Raj'Dur raiders will attack you. They don't always drop the key. If the first group doesn't drop it, wait ten minutes then examine the bones and kill the next group. Your quest will eventually update and you receive Historian Ganish's banner key.
Third kill any Alliz Raef Ew lizardman at ( -488, -130, -872 ) /waypoint -488, -130, -872 in The Sinking Sands until you get Historian Kaldara's key update. My quest updated while fighting the second group of lizardmen.