Need help.... white and dark green watery poo?

OK so about a week ago I noticed on of my hens favoring her right leg. I could tell it hurt because she would stay away from the others. So I pulled her and kenneled her in another area. Well the next day I noticed her poo was white and dark green and really watery. So I put her on some Duramycin for a couple days with no improvement. Then I gave her some scrambled egg which she ate fine. And then tried some oatmeal to firm up the poo but there's no change. She's lethargic. Decreased appetite. Thin. And has not laid an egg since confinement but has no signs of being bound or having any issues in that area. Research suggested worms which would be surprising having wormed and mite-d everyone just a couple months ago so I just now gave her some Valbazen as I did move everyone to a new area of the yard soooo maybe??? Another site suggested this could be cocci but in every case I've had here the cocci was clearly indicated by bloody stools. Does anyone have any other ideas?

Can Valbazen and Corrid be given at the same time?

Can anyone think of any diagnosis?