I'm really sorry you had to go through all this. I am glad, however that you've got closure and can rest easy knowing there was nothing you did wrong and nothing you could have done to save these animals.
The seller seems like a real piece of crap. After the necropsy results they should have done the right thing, taken accountability and refunded your money, as well as offered a sincere apology for all you went through.
Sharing the seller's info as well as details of this story in the inquiries/feedback section as well as fauna would be helping others to avoid this seller and all the unfortunate headaches and heartbreak you have had to deal with.
Anyway, I'm glad this nightmare is behind you (with the exception of any legal action you may decide to take) and at least now you know.
I truly wish you all the best moving forward. Good luck.