Search and Rescue

Kurzel is found in webbed victims inside Drak'Tharon.

These are quest strings that open up and lead to quests inside the instance:

strings start at 73

Good Troll Hunting opens up after completing My Enemy's Friend
In order to open that quest up you have to complete "The Thane of Voldrune" - http://www.wowhead.com/?quest=12259
(which is the end of the Voldrune three part line)

start with Good Troll Hunting (from Sergeant Thurkin, Conquest Hold, Grizzly Hills)
which leads to Filling the Cages (from Samir in Granite Springs, Grizzly Hills)
which opens Truce?
that leads to Vial of Visions
that leads to Subject to Interpretation
leads to Sacrifices Must be Made
which leads to Heart of the Ancients
which leads to My Heart is in Your Hands
which leads to Voices From the Dust
leads (finally) to Cleansing Drak'Tharon (which is a quest for inside Drak'Tharon Keep)

after doing up to Subject to Interpretation and Scourgekabob
(a single quest from Prigmon in Granite Springs, Grizzly Hills)
Seared Scourge opens,
which leads to Search and Rescue (another inside the Instance Quest)
after you do that quest (completed in the instance) Head Games opens and is doable
(use the quest item on the corpse of the second boss).

Note that while this quest says it can be picked up at level 72, the pre-req requires level 73.