martin castillo , from nuevo laredo , mexico , lost the ring in 2013 .
the precious accessory was discovered by daniel roark , who picked it up a year later while scuba diving in the same mexican resort .
mr roark , from massachusetts , began a global facebook campaign in the hopes of tracking down mr castillo and his wife jessica .
mrs castillo 's cousin heard about the campaign and messaged mr roark to tell him that the ring belonged to her relatives .