First half of the Wurmbone Key: ( -321, -145, -320 ) /waypoint -321, -145, -320 in the back of Pyre's room. (Unsure of strategy other than hit hard and fast. Pyre spawns adds at some point, which must be dealt with - blue and green AEs are suggested.)
Second half of the Wurmbone Key: ( -321, -145, 139 ) /waypoint -321, -145, 139 in the back of Frost's room. (Get him to damage a pillar and then keep hitting that one until it falls, he is nearly invincible until then.)
Map: ( -580, -118, -89 ) /waypoint -580, -118, -89 at the Forgotten Statue's feet. (If you avoid stepping in the circle, he won't attack you.)
Return to the Duality in Feerrott.
Take a druid ring to Jarsath Wastes. Once you're there, head south-southwest and pass through the cave at ( -850, 274, 1189 ) /waypoint -850, 274, 1189. After getting to the other side head to the boat to the southeast and speak to Erus Dal'viv at ( -757, -50, 1900 ) /waypoint -757, -50, 1900.
Head east to ( -1125, 124, 2004 ) /waypoint -1125, 124, 2004. Enter the cave and take the right fork then zone into Wurmbone Crag (Advanced Solo). (You have to kill all the named in here, no skipping.)
Speak to Erus in Jarsath. He is on a large purple masted galleon in the bay near the Wurmbone instances.
Zone into Wurmbone's End (Advanced Solo) via the left fork of the tunnel in Jarsath. ( -1199, 125, 2021 ) /waypoint -1199, 125, 2021 (You can skip all of the other named besides the end boss if you want to)
First Piece: Click on the Ancient Stone Icon at ( -315, -9, -334 ) /waypoint -315, -9, -334 (near the Shissar statues, out of aggro range of the named)