http://imgur.com/a/NZtwX
It appears to drop at random as i was in Felsoul Hold killing demons and my buddy was in Suramar killing elves and we both got the charm. The elf you talk to in on the highest ridge on the west side of Felsoul. You can take a path just south of Falanaar thatll lead you up to her, no need to do any crazy rock climbing. When fighting the bat just keep acting like your flying, keep towards the center of the vortex and as high as you can, you WILL need to glide to stay afloat, when he pushes you away two fel rushes and glide will easily get you back. No need to take Fel Mastery or go tank, very easy fight. Hardest part is staying in the air.