No he is it was confirmed in something called the World of Thedas or something like that. On short he was the priest of Urtamiel and one of the magisters which is the reason I asked when did they awakened.
You see in the books he says he for some reason became sentient and intelligent so that means that for some time he was mindless like every darkspawn. Cory the same must have been mindless in the first blight until for some reason what made them mindless stopped and became sentient and remembered his time as a magister.
I haven't read World of Thedas, so I can't argue on that specific topic. All I know is that in the Calling, he's displayed as an ordinary emissary.
However, it's very odd that a former Magister, one of the Seven, should not remember anything from his life or time of Ancient Tevinter, while Corypheus immediately remembers a great deal upon regaining consciousness.
I guess we'll have to wait to see whether more info will be displayed on the character in future installments.