Gotcha- if it was my little one, I’d see if I could hunt down a ferret vet, and look into the monthly shots (about $40 a month if I remember right), rather than surgery. It’s not a long term fix, but at that age more I’d be more worried about the quality of life they have left, rather putting her through the stress of anesthesia and surgery. You may want to check out Pet Assure, it’s not ferret pet insurance, but you do get a 25% discount on vet services (On the home page they have a list of their participating vets). Last time I checked VPI specifically excluded adrenal disease from coverage when I did my ferret pet insurance write up. I’m always surprised when a vet suggests an exotic vet- our kids are the third most popular pet in the US, everyone should be well versed in ferrets.