The Daily News can reveal the first photo of the 24-year-old Colombian call girl whose encounter with a cheapskate Secret Service agent ignited the agency’s worst sex scandal. One of the agents tried to brush off his girl, the single mother of a 9-year-old son known as Tania, the next morning with only $28 in cab fare. She caused a ruckus, demanding her full payment, so cops got involved and word reached the US Embassy.