The Harris County District Attorney's Office confirmed that a substance found in Lorenzo Salgado Araujo's van tested negative for narcotics and other illicit drugs. Lorenzo Salgado Araujo, 51, was shot and killed by an Immigration and Customs Enforcement officer while on his way to work after picking up his construction crew on July 7. The Harris County District Attorney's Office on Friday said its investigation into this is pending, which is wh…