Parvo attacks rapidly dividing cells - that's why puppies are so hard hit by it and also why in young puppies their heart is also affected. The most rapidly dividing cells are in the small intestine (specifically the villi - hair like protrusions that increase the surface area to the size of a tennis court!
)
The difference between diarrhea that can be held and that which can't is determined not only by the severity of it, but also where it originates. Diarrhea that originates in the small intestine, a dog can hold. If it originates in the large intestine, they have no control and cannot hold it at all. So, it makes sense to me that Sassy could hold it, and I wouldn't worry too much about that part of it making the disease worse (other than great compassion for how uncomfortable it would be for her). If it was bad enough, she wouldn't have been able to hold it, crate trained or not.
I did get Bamboo to cross his paws, LOL. I'm gonna request that he do it again in hopes it will help Sassy keep that EN down.
