I don't want to say something too controversial but I know some people seem to have gotten their eyesight better after switching to a carnivore diet. Eyesight is linked to vitamin A, I'd at least try giving her a multivitamin that is correctly dosed in vit A Example: https://www.reddit.com/r/carnivore/comments/f41hww/eyesight_...

Eyesight can be improved by tailored exercises: https://zhealtheducation.com/product/the-vision-gym/ I've seen these ones recommended by a personal trainer, I haven't tried myself

Hope it helps!