Stone Citadel bug?

Hi I have a question about Stone Citadel, I had two points in the boss atlas and I put one in +1 boss level (new mechanics more life, dont remember the correct description)
Now doryani has this mechanic at the end of the fight where he would hover over you and after some time slam down on you.
I remember in the campaign he was rather slow so you could already go to the edge of the circle and dodge out.
In the citadel he was always on top of me, and I have 30% movement speed +deadeye ranger speed. and I could not dodge the attack at all, is this a bug or is it intended that this is unavoidable?

Happened to me too tonight on my mnk. No way in hell I could get out of that aoe and got clapped. Really sucks given how rare the Citadels are to find...