Good husbandry and someone to care go a long ways with any animal. It is great that he is with you now, and has a chance of a happy life.
You can aslo try calling universitys of veterinary medicine. Around me there are no private vets that know squat about exotics. When I called one about pythons, they said.. and I quote "Yeah, we can look at them. I mean.. as long as it isn't anything serious. Simple stuff." I asked her if she knew how serious a respirtory infection would be in a ball python. Again a direct quote-- "Oh no. It would probaly clear up on it's own." I do not take my snakes there, but go to the local vet college instead. They almsot always have a exotics vet on staff.
Wolfy