I found the northern version of the Shroud Cabal Captain at 82.3N, 19.2W (he can be found anywhere in the northern mountains apparently.) He dropped a "Forager Captain's Resonator, This piece of crystal hums faintly. Its odd structure makes it seem like it was broken from a much larger formation of crystal., BU 10"
The coordinates on the crystal are: 51N, 33E. Telumiat Hollow Minions and Shroud Cabal Raiders inside, straight forward dungeon like the first.
Turn in the medallion in Sawato: You give Nomendar al-Rakh Node Leech's Medallion. Nomendar al-Rakh tells you, "Very interesting! This medallion can actually be used to directly siphon mana out of a node between ley lines, if one possesses the geomantic skill necessary... Not useful to one such as yourself, you understand, but I have colleagues who would find this medallion to be valuable and informative. All I can do is thank you with some practical experience..." You've earned 6,882,688 experience. (Level 116)