Kyle,
I can't say I blame you for not wanting to euthanize your snakes. However, they have definitely been exposed to some shoddy care, mites, and possibly IBD and whatever else Ashley may have floating around in her collection. Meanwhile, she's actively trying to get MORE cheap/free snakes, so there's no telling if she's been successful.
I'd make HER pay to test them. She certainly seems to be able to afford tattoos, piercings and has been actively looking to acquire more snakes. She has the money.
Kyle, you've been too nice for too long. This is ridiculous. She was responsible for your snakes while in her care. She's LOST several snakes, including one of yours, I hear. There was not full disclosure of the health of her animals.
This is a serious problem that can't be taken gingerly.
YOUR snakes SHOULD have been tested FIRST, and she should have paid for it.
Hers could have waited.
Although I think it's safe to say, she has not had her snakes tested AT ALL and she's lied to you.
If she didn't want to pay to have your snakes tested, I'd try to follow whatever legal protocol I could to recoup my losses. Small claims?
I mean, yeah it's time and money, but unless you are prepared to just cut your losses and let her have the snakes and cages, that's about your best option if you want to be able to move these snakes to other homes in the future.
Otherwise, you would be just as reckless as her to try to rehome them knowing their background.
The other option is to figure out a way to get them home with you, and do what you can to keep them separate from my existing snakes, even if I had to sell/rehome the current collection, or have someone take care of them temporarily.
This is a very serious situation, that I feel should be handled as such. There's no way to be sure the snakes would end up staying long enough in homes and not being bred right off the bat, to rule out any potential issues.