Agents in attack ad clear Sanchez BY TRICIA CORTEZ Times staff writer Two retired federal agents admitted Friday afternoon that Tony Sanchez and his former thrift, Tesoro Savings and Loan, "had nothing to do with the death of (Drug Enforcement Administration agent) Kike Camarena." One day after Gov. Rick Perry and his Democratic challenger Tony Sanchez acknowledged the public's disgust with negative ads during their Dallas debate, the Rick Perry campaign launched another attack ad statewide Friday. The ad alleges that Sanchez, through Tesoro, was linked to the Gallardo drug cartel and the death of DEA agent Camarena Hector Berrellez...