All on purpose! I call it now, Magatha will be in the seige of orgrimmar raid and they have been working together all along. With Garrosh trying to kill Vol'jin and even attacking echo isles it cant be a coincidence he won a duel he could have lost due to his weapons "Accidentally" being poisoned, and think about it, how did magatha get away with that? No way a huge thing like that would have been shrugged off and she didn't even appear later in cataclysm after thousand needles. Magatha will be a boss in seige of Orgimmar, and if not atleast that theory will be proven!