Thanks for the comfort everyone, I do realize that I don't think she's going to make it, but she is a fighter!
I'm about 99% positive she had heat stroke the last time. We're in northern NSW and we had a whole string of about 2 weeks of cold weather and storms, then all of a sudden one hot 30+ degree day, which is the day we found her passed out in the coop.
When she got the cold water bath, she went from the edge of death to open eyes and slightly curious in the course of about 10 minutes, so I am pretty certain that's what it was.
I think perhaps after the heat stroke she was still weak enough to be susceptible to any other diseases around and that's what got her. She was fine for about 1.5-2 weeks after the heat stroke, acting completely normally.