It was a “tribal” marriage to his first “wife”. If he had a tribal marriage, it was most likely an Islamic marraige since he was Islamic. That being said, why would he have to do anything with the first wife just for taking on a second?
I guess it would depend on where he was married. Are Muslims who already have wives and families in other countries allowed to come here and marry American citizens? I'm not sure what the laws here are, or what they were back when Barry's parents claim they were married. Nobody really knows if they every actually married, do they?