premise: Gordon has only visited Singapore, Corey has only visited Sri Lanka, Joseph has only visited Cameroon, Bruce has only visited El Salvador, Jimmy has only visited Slovenia, Randall has only visited Lesotho, Mike has only visited Venezuela, Tyrone has only visited Mauritius, Cory has only visited Peru, Nathaniel has only visited Palau, Jerome has only visited Tajikistan
hypothesis: Dustin didn't visit Tajikistan