I am on a 47 priest in tanaris. I went to do the little arena questline in gadgetzan using my 85 on other account to help clear it (At Dr. Dealwell). I got the 1st 3 done out of the 4 or 5, then he stopped giving quests to my priest entirely (bug 1). He still showed as having a quest available, but didn’t really.
So, I check on my 85 to see if the 4th one really is there or not. He does have a 4th, but somehow it it the quest The Amphitheater of Anguish: Yggdras! (requires level 77) from Zuldrak in Northrend. Curious and confused, I accept it. He has me fight the mob from the 1st Tanaris arena quest over again (named Ginormous) and it works, the quest completes. It shows as a northrend quest in my log and I confirmed I was able to hand it in at the Amphitheater of Anguish in ZulDrak at Wodin the Troll-Servant.
Are you kidding me with this Blizzard? I am actually impressed with how bad this one is.