I don't think you can treat blindness.
I have a store bought quail hen that was among the first ten quail chicks that I bought when I started raising quail, she's blind in one eye, and I didn't realize it until she'd been here for a couple days. The affected eye is huge, swollen, and always has been. It doesn't bother her, so I don't let it bother me. I've named her Ace, and she is the only one that I've named. She's incredibly docile with an easy-go-lucky attitude, unlike most of my birds that freak out when I add water or add feed. Just saying... being blind since birth isn't something you can just "fix", but you shouldn't see it as a quality of life issue for your bird either.
It's probably a birth defect, and is, I'm quite sure, untreatable. Just ignore it. She might be a bit more nervous than some, since she can't see halfway and her peripheral vision is limited, but she should be able to function relatively well.