Latest (03/10/2016):

Everything else not in this quote is to be considered as obsolete/wrong leads.

remeber to spec Outlaw or the dialogue option won't appear

Ixzo managed to do the entire trip. Here's the recap of what's known and what's still on debate, but you will have all the needed ifnromations to do the entire thing by yourself.- AK5 is the trigger for the left binding to drop from Dargrul in NL. Can drop at any difficulty and it's not a 100% chance.- AK6 is the trigger for the right binding from Ash'Golm. Again difficulty doesn't matter.- reputations areneeded. Confirmed multiple times for right binding and we have proof HERE(pic) and HERE(reps) for left binding.- you need either one of the bindings to start the quest, doesn't matter which one you get first.- Thrymjarys will give you the quest through a new dialogue option when you have one binding -. Ixzo himself just stood there a while, you can try to spam login/logoff and see if the trigger is forced.- Enjoy your quest chain and Thunderfury appearance! Thanks everyone for the support and help in the search.NB: some people are experiencing bugs with the quest/dialogue with Thrymjarys - either choosing the "wrong option" or it disappearing randomly and having them stuck on that point. First make sure you're specced Outlaw but a fix for that is to simply queue/play one arena skirmish and once you're out the dialogue will appear again letting you complete the steps.