I hate to be the voice of doom but the green poop tells me that there is a liver issue going on. Mareks will attack all of the bodies systems including the liver, the nervous system and the immune system. What it seems to me is going on is that she has Mareks, and its causing neurological symptoms, attacking her liver and depressing her immune system which is allowing the coccidia to run rampant. I would call a vet, aprise them of the situation, ask for some albon without an office visit or see if the feed store has any sulfadimethoxazine (not a thiamin inhibitor) and keep her as comfortable as possible until the Mareks reaches its inevitable conclusion.
As a Post Script, in my opinion, I would never give amprolium (corid) to a bird with wry neck or some other possible B deficiency issue- you're just shooting yourself in the foot.
PPS, you could also try some milk thistle (available at CVS) to help alleviate the stress on her liver.