I did it at level with 5 paladins.

Nazun is the dragon, right? Walk backwards in a circle (I don't remember if I actually walked backwards, turned my back to him, or strafed sideways) so your 4 rets are always attacking from behind the target. Use your fire resistance aura & heal the tank as needed.

After a half-dozen wipes I read about that strategy & it worked for me.