Socks’ Corneal Ulcer Treatment

Hello, my dog socks is 7 years old and we are from the U.K.  Over a week and a half ago we took him to the PDSA vets and they told us he had a corneal ulcer, they gave us an eye gel and some cream to give him as drops once a day. They did not stress how important or serious eye ulcers were in dogs. Socks is a difficult dog, so we were unable to get the drops in without being bitten as he was clearly in pain and scared, we took him back to the same vets to explain we couldn’t do it, who gave us drops to try and didn’t inform us how serious it was yet again, we tried this over a few days with no luck. We then decided to try a new vets which we have to pay for, in order to get a second opinion, they had to sedate him to check his eye and advised us that it was a deep ulcer that needed either £2,000 surgery with £2,000 aftercare or a £900 eye removal, we ended up with a £175 bill from this vet, and they referred us to a specialist eye vet a 2 hours drive away so we took him as soon as possible. This vet bill then added another £560 for this trip, as they also had to sedate him to ensure what the first vet said was correct, gave him fluid, injection and tablets, they advised us that it is not as deep as the first vets advised but he NEEDS the drops administered, so we are going to try our best to do so... if this doesn’t get better in a week, he also needs the £900 eye removal treatment, on top of the bill which was £735 today. I am kindly asking for help in any way which you can, I would greatly appreciate it, as this is a cost we weren’t prepared for and had already had to be paid, we have all of the receipts as proof. We are from the U.K., so usually use the free vets (PDSA) as my mam gets benefits for her disability, so we have never needed pet insurance, but we needed a second opinion as we got nowhere with them so had to go private for this. We are going to look into getting pet insurance after this due to the treatment we received from the PDSA and how expensive this is going to be. This has been so stressful and we just want him better. Thank you.