K.U.
As a vet, I would say it sounds like you are already doing everything that can be done and short of seeing a vet who is an opthomology specialist (yes, they do exist) and getting their expert second opinion, surgery (whether it is to help the cornea to heal or to remove the eye) is the next step. As for which you should choose now, nobody can say. Almost everything in medicine is a gamble and we can't 100% predict the results. I always have to inform people of the possible risks and outcomes for their pets before allowing them to consent or decline anything. If your vet feels she has an 80% chance of the eye healing with surgery, that's pretty darn good - but if you are not financially prepared to potentially do 2 surgeries, I would just have the eye removed. Dogs can do just fine with only one eye (one of mine is living proof of that) and she won't be in any pain. As long as you understand there is the potential that she would need to have the eye removed if the first surgery doesn't go well, then that's all you can do. Oftentimes our job as vets is to offer options with as much information as possible and let the owner decide from there. Nothing in medicine (human or animal) is 100% certain.