The cause and manner of death of16 & Pregnant alum Jordan Cashmyer remains a mystery more than a week after her shocking death. As of Monday morning, the 26-year-old’s autopsy had still not been completed, Radar can exclusively reveal. The executive assistant to the Chief Medical Examiner for the state of Maryland, where the MTV star died, could not provide further details, as the case is still under investigation. Autopsies typically take several hours to perform and can produce preliminary results in as little as 24 hours; however, the process may take up to six weeks if other tests – like t…