Can an American actually advertise a European?

So my friend had scammed an American and accidentally slipped his number out. The American wants to go to his cops now in the guidelines of Fortnite is that account trading is prohibited.

You enter into a contract with Fortnite or Epic Games. A violation of AGBS is a breach of contract. Is only the question of whether the contract is valid under German or American law. Police work together, e.g. Interpol.

Everyone can show everyone. Nationality does not matter.