I came up with some hints that Garrosh might be siding/allying Mogu against his Foes in final fight.
1. Here is the new Graphic Novel that is "under wraps" called "World of Warcraft: Bloodsworn", but we Blizzard shared summery of this novel. Which say this:
As the Cataclysm rips through Azeroth, Warchief Garrosh Hellscream orders the best warriors of the Horde to come forward and serve in a new army, lest their foes in the Alliance sense weakness and attack. We meet these warriors as they come forward - from very different lands, backgrounds, traditions...Will they be able to overcome their deep differences and work together to serve the Horde, especially when challenged by a powerful, unfamiliar race claiming to be the real rulers of Azeroth?
And the mogu claim to be Real rulers of Azeroth, Yes? Yes.
World of Warcraft: BloodSworn
a.Yes it says clearly that "though Bloodsworn takes place prior to Mists of Pandaria," but we face different situation now. We are in middle of Mists of Pandaria an mogu fit perfectly in this creatures description. As the book is in Wraps yet, writer might add mogus in it!
It is also only Guessing that Bloodsworn is prior to Pandaria ! The summery just dont includes any of Pandaria facts no to contain any spoilers, or ruin book itself, because as we knew Mists of Pandaria was spontaneous expansion. and the time in development doesnt changes anything they can always ADD. Or book might have introduced them from different corner. So this "Prior" thing doesnt change anything.
b. Or Garrosh (not directly Garrosh, might be Malkorok) might found These guys earlier then others did. I suspect Malkorok is not quite ordinary orc and might know Mogus long ago (but tha onl Imho). But next 2-nd argument contradicts with this B. theory, that Garrosh had known mogus previously.
2.Garrosh is quite interested in these new found "Mogu." Link
He might have contacted with them after failing to reclaim power of the Bell. He has one big slave Mogu, who, as i know, is still alive.
Garrosh is known for his cowardly ways of fighting (Focusing Iris, Krakens, Magnataurs). "Enemy of my enemy is my friend".
Source : http://www.wowpedia.org/Garrosh_Hellscream
He learns from Malkorok about the mogu race and takes a special interest in the iron-fisted rule of the mogu and their technology (remarking to Malkorok that he has much to learn from them), being particularly attracted by their ability to create new warriors and fuel emotions to their height in order to drastically increase battle prowess.
So what do you think?