It happens. Trust me, I did my druids boots, only to get invited to do Freeti in SolB five minutes later, first kill GEBs, roll was mine. /sigh I wasted alot of time but I still do the quests, just to say -I- did. Even if that holds no satisfaction to anyone but me!
I did this quest. I hunted for days in the Scarlet Desert until I found the Vial of Firewater I tried killed Sambatas at the hopper cave in Dawnshroud Peaks when it seemed that only the rockhoppers were ever up, and had to beg for the Iced Nectar when I saw the Samabata Nectar Collector run past me getting pulled by another group. I had to trade 15 twilight quest items just for the one Mark of Temper when I found someone finally selling it. And, I paid 200 plat to buy an Astral Jewel. After days and days and lots of money worth of work I finally got the cloak listed above. It was to be my upgrade from my bear-hide cloak. ^_^ Right after getting my cloak of detonation I spotted a named shadow on the island in right near where I did the quest. Thinking to collect more twilight items I killed this frenzied shadow I found. Guess what I looted.....
Oh my gosh! All that work and I immediately stumbled into a cloak that is just as good as the Cloak of Detonation, and it was just sitting there all along right next to the quest guy! /cry