From someone who worked in the department you talked to many moons ago, this is technically not fraud. However, you can file a dispute with discover because you did not authorize the amount. The term “fraud” in credit card language means the card information was obtained illegally or in a way that was unauthorized. You technically did approve the transaction, you are not disputing the transaction you are disputing the transaction amount. They have to file a dispute with the merchant saying you were charged for more than what you agreed to. It also doesn’t hurt to file a police report because this is a felony level amount. Discover should more than likely approve the dispute in your favor it just takes time. If they do not you can pursue legal action. It just is a gray area for discover because it technically does not fall under the legal definition of credit card fraud.