Would you be able to answer my questions regarding international employment contract law?

I actually have 4 very difficult questions. A friend of mine who lives in Qatar, and works as a graphic designer, wants to sue an American who violated their work contract. The contract was first signed in Qatar by the designer, and then in the US by the client. 1. Would a US court recognize a judgment, and monetary award, issued by a court in Qatar? Perhaps under the Federal Arbitration Act or the New York Convention? 2. If the lawsuit was brought in an American court, would a state or federal court accept jurisdiction? Or would the fact that Qatar is not a party to the Hague Convention prevent the designer from bringing a civil action in the United States? Please quote specific supporting statutes. 3. If the suit was brought in an American court, would the designer have to appear in court to testify to the validity of his signature, or would a signed affidavit be sufficient?