hmm.. this is very curious.. I ran down to temple earlier today as I heard rumour one of the named for the new HQ was there...
He sure was there, white con and hailable tho, no where near agro (I actually mentored down and killed a named NPC in same room with Xyfkl standing watching.
I never hailed him, this might be what ye ran into, someone with quest activating him, wipes and heads off, leaveing a very moody dragon behind to take his anger out on anyone else.