Common questions are is there any drainage from the eyes or nose, mouth, or foul odor - suspect coryza.
"Ocular Marek’s disease symptoms are irregularly shaped pupils, gray or cloudy eyes, difficulty seeing, and finally total blindness in one or both eyes. A chicken’s owner may realize something is wrong when the chicken doesn’t respond to human approach, or when it has trouble picking up small food items. It has more difficulty eating, drinking, and navigating as the disease progresses. Since chickens exhibiting symptoms of any form of Marek’s suffer and eventually die, the most merciful option is to humanely euthanize them as soon as the disease."
(Copied info)
Mycoplasma gallisepticum: signs can include foamy eyes, sneezing, nasal discharge, swollen eyelids and sinuses, reduced egg production and gasping in chickens, turkeys and pheasants, swollen sinuses in waterfowl.
Images -
https://www.google.com/search?q=Myc...VATkQ_AUoAXoECAIQAQ&biw=753&bih=1205&dpr=2.13
And if it's an eye worm, you'll see a squiggly thing on the eye.
I swear it was vet rx I had and put in my Blue's eye once when it was infected, and it cleared right up. That said, whatever it was had instructions for eye use and the instructions online now do not, so I'm afraid to suggest it.

I'd def isolate until you sort it out.