The hen with Sour Crop what's her poop like?
Is she having any respiratory symptoms or does she have any of the yellow cheesy material inside her beak too?
As for wormers - you may find this helpful. Safeguard (Fenbendazole) given in approved dosages doesn't have a withdrawal period...
Could be, but if there's crop issues, possibly thrush?
I still don't have a clear idea of symptoms, but if the eye is swollen and there is respiratory symptoms too - possibly the cause would be respiratory disease. Quite a few possibles here.
Can you take a look inside her beak and throat for any canker, yellow material, mucous, etc.?
Look inside her ear too.
Looks like she has a lesion on the outside of her beak?