The sitting on her hocks can be a symptom of vitamin B 2 (riboflavin) deficiency. I would give her half of a super b complex tablet which contains B 2 and other B vitamins daily into her beak or crushed into some food or scrambled egg.
I would not inject anything into the vent since that can push fecal bacteria up inside the oviduct. But just using the polysporin or honey on the outside will keep it moist and from drying out. Since there is damage and blood, I would not try pushing anything back in, but wait until swelling has...
Many times the state lab will send you a prepaid shipping label to send the body overnight by Fedex or UPS. If you talk to them and stress that it is a backyard bird, they might be able to help you.
What state are you in? If you can wrap the body in plastic garbage bags and keep it cold on ice in a cooler or in the refrigerator you can call the state vet lab in the morning for a necropsy. Sorry for hour loss. Here is a list of state vets to call...
Oh yes, fowl pox. It is a virus spread by mosquitoes, and lasts about 3 weeks. It is more common in the southern states and tropical areas. Most chickens recover, and will be immune to that type of chicken pox in the future. Secondary infections, and the more severe wet pox can sometimes occur...
X2, it sounds like stridor. I had a hen who would do this after literally inhaling her feed. It usually cleared in a few hours. They can usually cough or shake their heads to clear their airway. Let us know if this goes away by morning.
A bad odor and very swollen eyelids with pus does sound like coryza. Sulfa antibiotics such as sulfadimethoxine or trimeth sulfa are commonly use to treat it. But the pus does need to be removed. Here is a video of pus removal:
I think @casportpony has a link about cutting into the sinus...
I am sorry, but I am always confused with the Aquasol dosage. It is meant for diluting in water. If I were to give it and use half as much, I would use the same amount of water, and give it orally, not in her water to drink. Repeat for 5 days for gapeworm treatment.
Has she started laying? How often, and when was last egg? Could she be egg bound? Is her tail position up or down? Is her comb red? Can you mix some water in a small amount of chicken crumbles or pellets and make a mush, then offer that with a little scrambled egg to her beak. Any pictures of...
I would just take it back and exchange it for the SafeGuard liquid goat wormer or the equine paste, and use the dosage of 0.23 ml per pound given orally for 5 consecutive days. Be sure to shake the liquid goat wormer very well for each dose, since it is a suspension.