Glad you could figure out how to go forward. Hope all goes well and that he has a great recovery!
Procedure-wise, I would think they'd look at her eye, maybe peek under her eyelids a bit. Maybe rinse with a sterile solution. Do an eye-stain and look in her eyes with a bright light and little magnifier for a closer look. They would likely also probably prescribe an antibiotic ophthalmic lotion for you to apply at home. That's basically what my vet did for my piggy's eye injury.
For after-care, I'd suggest trying to keep his cage super clean. Also, I use a blend of orchard grass and timothy hay by oxbow. Orchard grass is softer than timothy and has far fewer twig-like poky bits. Bit of a different nutrient profile - you can find lots of info that compares protein, fiber and calcium content of hay types if you want to know more.