It looks like she needs to be treated immediately for Coccidiosis.
Go to your local feed store and buy some CORID.
Corid dosage for Cocci is 1 1/2 teaspoons Corid powder per gallon or 2 teaspoons of 9.6% Corid liquid per gallon Give for 5-7 days - make sure this is the ONLY water available during that time period. Mix a fresh batch at least once a day. After you finish the Corid treatment follow up with some probiotics/plain yogurt and poultry vitamins.
Since she is crashed out, separate her and give her the Corid mix by eye dropper or syringe, drop a little by her beak so she can take it in. It will be slow going, but you need to try to get as much in her as possible. Don't worry about food at the moment, just get her hydrated with the Corid water.