[Shadowmoon Valley] "Ally of the Netherwing" quest never appears after killing Zuluhed

[CatValle]

Wowhead quest link: 10872
WoW Freakz quest link: ?
Bug description: there seems to be a problem with the last two lvl70 quests of the Ally of the Netherwing quest chain. (The one given in Shadowmoon Valley started by Mordenai advancing players from hated to neutral with the Netherwing faction)
After completing the quest "Zuluhed the Whacked" killing the boss and freeing Karynaku, the following quest, given by Karynaku itself right after completing the previous, never shows up (which would be the Ally of the Netherwing, last one of the quest chain, consisting of returning to Mordenai .) This is a great questline and a shame it cannot be completed to, later on, aquire the Netherwing Reins and stuff. If you could please adress it, thanks in advance!
Official WoWWiki link to the complete questline Hated to Exalted: http://wowwiki.wikia.com/wiki/Netherwing
Proof: This is the first time ever I use this forum, I don't know how to put screenshots or videos or how could I prove this issue but it is real and I've met other players in game who are stuck in it to.
Thank you![/url]