Want to know who killed JFK?

The narrative you've presented combines elements from various conspiracy theories surrounding the assassination of President John F. Kennedy. Let's examine these claims:

Malcolm "Mac" Wallace's Involvement:

Malcolm Everett "Mac" Wallace was an economist for the U.S. Department of Agriculture. Some conspiracy theories suggest his involvement in Kennedy's assassination, alleging he was hired by the CIA and Vice President Lyndon B. Johnson. However, these claims lack substantial evidence and are not supported by the official investigations.
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Driver William Greer's Role:

Another theory posits that Secret Service agent William Greer, who was driving the presidential limousine, fired the fatal shot that killed Kennedy. This theory is based on interpretations of the Zapruder film, which some believe shows Greer turning around and possibly firing a weapon. However, this interpretation has been widely debunked by experts, and no credible evidence supports the claim that Greer fired a shot.
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Conclusion:

While these conspiracy theories have been discussed over the years, the official investigations, including the Warren Commission, concluded that Lee Harvey Oswald acted alone in assassinating President Kennedy. Theories involving Mac Wallace and William Greer lack credible evidence and are not supported by the findings of these investigations.