 After O'Sullivan published his book, assassination researchers Jefferson Morley and David Talbot also discovered that Campbell had died of a heart attack in 1962, six years prior to the assassination of Kennedy.In response, O'Sullivan stated that the man on the video may have used Campbell's name as an alias.He then took his identifications to the Los Angeles Police Department whose files showed the men he identified as Campbell and Joannides to be Michael Roman and Frank Owens, two Bulova sales managers attending the company's convention in the Ambassador.