The location of these Stranglethorn Raptors is quite deceiving, they are NOT slightly north of the Grom'Gol Base Camp (these are the Lashtail Raptors).

North East of the Tkashi Ruins (where you do the Bloodscalp Troll quest (Alliance side)) you will find the Stranglethorn Raptors.

Hope this helps, I was wandering around for a looong time.