I was in a great group last night, we had her down to about 3% and failed, my best attempt yet. I think if the update had not happened we might have beaten it.
The problem was she seems to be either attacking or switching sides like every 3 seconds. There is almost no time to attach her as you are constantly running to avoid one of many large attacks of hers or having to run across the platform only to have her start yet another attack so you have to reposition again. I don't remember all this repositioning happening before the update.