If this were my chicken, I would: 1. stop the herbs/ACV immediately; 2. call local farm stores to see if anyone has Tylan in stock; 3. If you can find Tylan, buy a clean syringe with a fine gauge needle and give an injection. It's a broad spectrum antibiotic. There are videos on YouTube on how to administer an injection to a hen in the breast; 4. offer her cooked egg twice a week for an extra protein boost (i.e. 1/2 egg is sufficient); 5. For deworming, mix some food-grade DE with the cooked egg for 2 days straight. Wait a week, then do it again. We did this with our flock after reading how to reduce poop on eggs on a blog post, and it worked. Literally, the next day, the eggs were clean. DE is like asbestos to the lungs if inhaled, so don't let it get airborne and only mix with a moist food; 6. Offer some grit in case she needs that for digestion; 7. Make sure her feathers aren't covered with poop. If so, bathe her with warm water and dry her off.