Hi, This looks so bad, I didn't want to even try to give advice.
There is a Terramycin eye ointment that is sold at farm supplies.
An antibiotic ointment would not affect healing of viral infection but would address a possible bacterial and the ointment/salve would also help protect from environmental issues, e.g., dust wind or drying out. Although, pox or blisters are in need of drying out to heal, but with it being right on the eye like that, I'd opt for the ointment.
Any human meds at home for the eye or ear? Guess what....same stuff. Just make sure your meds do not have "caines" in them...chickens, I hear, are allergic to them.
I used a ciprodex with prednisone ear drop med for my roos eye and it helped save his eye.
Use an eyewash containing boric acid solution, from the drugs store OTC, to rinse and clean eye in between applications or at least until it starts to look like there is some improvement. These are just my thoughts on this matter.