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[spilota_variegata]

You're keeping it at good temps, feeding it meals that are not too large, providing it with hiding spots and trying not to handle it unnecessarily. Sounds to me that you're doing all the right things. Sorry if you've already stated this but have you contacted the previous owner to ask if this problem was evident prior to your purchase? I hope it's not a congenital condition - one that most likely can only be diagnosed by an expert. Noone on this site will be able to give you an informed decision without the right tests. Bringing up his meals may have serious consequences in itself. One more thing, are you feeding all the snakes with the same food? I had a problem a long time ago with contaminated food.

I hope the little fellow pulls through. I wouldn't wish the death of an animal on anyone.