Well I ain't sure if I have ascended or not because I did kill her but I also died too. I got 50, 000xp and i got spawned back @ Aurgury Rock now im not sure if i ascended or not.
After ascension you're supposed to be teleported to Dragons Lair. Only if you fail you will be sent back to Augury Rock. But in that case you don't get the XP reward off course.
I had this exact same thing happen to me on my first character.
I killed my dopple and I died at the same time. It acted like I ascended and I did get the XP but I went back to Augury Rock.
I had to go and do it again so I could get to Dragons Lair.
Thats strange. I had that happen to my Necro but I did go to the Dragon Lair. My Necro died same time as the dopple. I got the 50k exp. I actually thought that my character died before the dopple, but as I died, the cut scene started and I got the exp and was then sent to Dragon Lair.