Help us save Jax, our pittie rescue

We took our dog, Jax to the groomer after noticing some itchy red spots on his back. A week later, his back started opening up and sores appeared, so to the vet we went. A skin scrape was done and he was put on steroids and antibiotics. A week later we returned to the vet, as the sores had spread. He was sedated, cultures and biopsies taken, a full blood panel taken and put on new antibiotics. Another week went by, and we returned yet again. This time the vet administered an ACTH test, to check Jax' cortisol levels. As we waited for results, we took him to another vet for another opinion. They gave up injectable, very strong antibiotics, ointment for his skin and took urine. All signs point to Cushings Disease. It is treatable, however a horrible secondary infection is spreading all over his back. They are gruesome, horrible, oozing sores. It is a fight for his life. We need help to pay for a dermatologist, an Internal Medicine doctor, a dermatologist & the pills to control his cushings. The pills will be very expensive and aggressive.
If you can donate, ANYTHING will help! We have a 4 month old daughter and we have already spent $1,200 dollars just figuring out what the main cause is! Please consider donating! We rescued Jax 2 years ago at 7 years old, he is huge part of our family! We would love to give him a longer, healthy, spoiled life! Thank you!!!