I am a breeder who sold a puppy to a customer who is requesting a w-9

I sold a puppy to a customer who 3 days later put the pup to sleep.  She said she owns a business and is requiring a w-9 from us with my ein or ssn.  $350 of the purhcase was on paypal for deposit and the remainder was cash, which I claim on taxe

 

Am I required to provide that to her for the purchase of a puppy?