She's unwell because she been bred to lay more eggs. Most of the Ex Batts will die from reproductive issues. I can only deal with the obvious problems.
As I mentioned on By Bobs thread, the Ex Batts are dead hens walking. There is nothing I can do apart from get them out as much as possible, feed them decent food and kill them if they look like they are suffering. Fortunately so far the five that have died so far have died quickly as I've been told they will. They are not strong enough to fight for life for long.