I just found Luna dead.

[Bogertophis]

... I had all of my rainbow boas die from similar symptoms, and when I talked with a representative at the University of Florida, one of the vets there said he's noticed rainbow boas tend to have a strange condition...

First, I'm so sorry for your losses as well. How long has it been? How many did you lose? That's just so sad, they're such beautiful snakes.

Is this thought to be an inherited defect of some kind? Or something contagious, if you (or they) know? Thanks for adding your information here,
"mysteries love company"- but I hope the vets can figure out what's causing this sad situation & can help in the future.