So the last Warglaive of Azzinoth dropped after 3 attempts. The first after 2nd attempt. After which I just HAD to see the drop chance of them on Wowhead. Apparently I was EXTREMELY lucky with them being a 5% drop chance. And considering that you need TWO DIFFERENT glaives (main & off-hand), I might as well have gotten the same warglaive twice which wouldn't have completed the set.