Goldfish with abscesses?! need help

[fshfshfshfsh]

one of my young orandas developed some weird abscesses all over his head/one grew inside his eye and I'm getting a bit desperate to find a solution for my poor buddy!! he's been in quarantine (10 gal) with daily water changes and aquarium salt, and it's been nearly 2 months with no improvement at all- I've tried multiple broad-spectrum antibiotics over the course of those 2 months to no avail! Is there anything I can do for my poor buddy that will help eliminate these bumps? They are soft squishy bumps that can pop (I've popped a few of the external ones before but they grew right back), I do not know what to do...help would be greatly appreciated!!
His original tank was a 75 gal with 2 other fancies (who are totally fine) with clean water (0 ammonia, 0 nitrite, ~20 nitrate)

 

[Colin_T]

What are we looking at, the white bit around the eye or something else?

If the fish has sores that aren't healing, it probably has something wrong with its immune system. It could be run down due to worms and gill flukes, or it might have some sort of internal issue, or it might just be a genetically weak fish.

You could try deworming the fish and adding lots of plant matter to the diet.

Maybe take the fish to a fish vet and let them take a swab of the infection. They can then try to identify whatever is causing the infections and they might find a drug resistant bacteria or something else.