Always remember that when acting as a court of appeals the Supreme Court isn't judging the basic case so much as it's judging what lower courts have done.
Whether the email is fraudulent is an issue for the lower court. SCOTUS isn't there to judge the evidence. It's there to judge the question presented from the lower court.
So SCOTUS is there to scrutinize what the 10th Circuit did while assuming its reading of the facts to be correct for the sake of the argument.
https://www.supremecourt.gov/docket/docketfiles/html/qp/21-00476qp.pdf