Advice needed for blind leopard gecko

[geckocrazed]

hello everyone,
I am currently seeking advice.
I got my first ever leopard gecko in october, he had been someone else's pet and is almost three years old. when I got him he had not been looked after properly and did not have heat, a proper hide, or proper substrate; his substrate had been sand his whole life. the moment I got him he wouldn't keep his eyes open, he would just walk around with them shut. I thought maybe it was the poor care he had received and immediately bought him a heating pad, proper substrate and a large hide. I had been told from the previous owner he could eat like crazy and loved mealworms, so I bought mealworms. which he wouldn't eat, he would just hide. then I noticed shed had been stuck on his eyes and it looked like it had been there for a while, I called numerous vets but none near me will see exotic pets.
I eventually found a vet willing to help, the drive was only about an hour, it was an exotic vet who claimed to specialize in geckos. but when I got there she said she had only seen two geckos and basically said there was nothing she could do except maybe vitamin shots. she said that we had been taking good care of him for the short time we had him. she recommended we use sensitive eye drops to maybe help get the shed out, which we did, to no avail. he wouldn't eat so I had to feed him wet food through a syringe. after two months of syringe feeding, I decided to try crickets. which he LOVES. he now eats crickets every two days and actually moves around a lot more than when I got him. however, no other vets can help, the nearest vet that we have not been to yet is two hours away and they can't do eye surgeries on geckos, which I believe he needs. he would need to be sent away for the surgeries, these vets are so far away I simply can't do that. his eyes are so bad and I feel so bad. I know this isn't my fault and Iv'e tried so hard to keep him as happy as can be, but I'm scared he's in pain. he can't see out of his eyes, he has trouble feeding so now I buy canned crickets. the owner claims he was in perfect condition the day she gave him away, I don't want my money back, I just want a happy, healthy gecko. any advice would be greatly appreciated, I just want to help him. this is my first and only gecko and I feel like it's somehow my fault which is discouraging me from buying another gecko. as mentioned before, ANY advice would help so so so much.