Does it smell bad now? Was the drainage clear or green like pus? It's possible there was an infection that caused the eye to rupture when it was draining. Priority now would be to make sure there's no infection now, I know you can use Bausch & Lomb eye rinse and apply Neosporin or other antibiotic ointment as long as it has no pain relief in it. I've only dealt with eye problems for my dog so Idk what else you could do for her. Maybe look up what medicine is used for treating eye infections in chicken and see if you can find it at your local animal stores? I saw a video not too long ago where a woman was draining a build-up around the chickens eye and it was just swollen shut, I'll try searching for it so you can see if it looks similar to that.