IBD researchers have commented that specimens sent to them from boa breeders as "control" animals, supposedly free of the disease, ended up testing positive for IBD.
As for pythons passing quickly from the disease - that's only true for some species. Some pythons species may end up proving to be asymptomatic carriers.
For sure. Just because it's from a breeder doesn't mean it's immune from IBD, but at least you have a source to go to if you do have a problem in the future.