So, to paraphrase, ‘me, me, me! mine, mine, mine!’
That’s your defence? I’m not persuaded.
People are very emotionally connected to their animals and this person no longer feels good about sending hers to you. That happens for many reasons in a sale. Have the dignity to allow her out of the sale without punishing her to the greatest extent you can.
By doing all you can to hurt her financially and emotionally, you play the role of ‘litigious American’ to the hilt.
The decent, adult thing to do here is to get your money back and leave the seller in peace. Don’t make it yet another SM flame war meltdown freakout. Just quietly unwind the transaction, get your money, and walk away. Both parties will be in the same position as before the contract was made and that’s a great outcome.