They do have a record of the purchase. That record show's that a unknown name customer purchased specific catalog number item on certain day at a certain time in a certain store for CASH. Unless you purchased the extended warranty, there is no record of your name on the sale. Since you did not purchase the item with a credit or debit card, there is no way to link you, as an individual to the purchase.
If you can give them the day and the sales associate remembers the purchase, they might be able to link you to the purchase.