I haven't done her yet, so don't get upset, just thinking out loud. I went to twenty-totems website and I thought I saw something about some mobs being nature or magic immune and what do you plan to do about them. I think it was mentioned to use shocks and melee. So I built my team around melee and shocks. I use mail. I use stam/int/spirit. I don't care about spell damage. I don't care about casting. I use lightning bolt about 2-3 times on a pull and then not again until the next group. All 5 of my chars can take pretty good hits. They all use 1H or staff. All can heal pretty good. So hopefully I can just shock her and run her around I don't plan to stand in her pushback aura all day. That seems just bad. I went with a heavy melee PUG before and they were good, but the healing needed sucks hard. Then I went with all ranged group and the it was a joke how easy it was. So since shammies can't range her, I plan to run around like a chicken with my head cut off. Hopefully if she doesn't stop much, she won't push back much. All frostshock and whoever has aggro, starts running away. Hopefully she just runs after that one. Others frostshock and whoever has aggro runs away. Yeah, it isn't pretty, yeah, it might totally not work. But that is my first thought.

My next thought is to cheat and sub in a ranged. I got a 50 hunter and a 52 hunter to sub in 2 spots. Both have pretty good pets to tank. Send in pets, get aggro and flame shock and heal until dead. Then I switch out hunters and put in different or just do one hunter at a time. Again, not sure if it will work, it is just my second thought.

My next part is maybe her pushback is nature. Maybe you can get a nature pot (aborbs nature damage) and use nature resist totem and just melee her down. Not sure if that works, but just my 3rd thought.

She is hard, but she has nice loot, so don't give up. Just find a way around it. Good luck.