I haven't watched it, but it sounds like the same tired rehash of basic CTer 101 in the JFK assassination. Even had there been a LHO trial, the very best that could have resulted from a CTer perspective is that Oswald was found not guilty. Such a verdict, however, would not preclude his being guilty or somehow prove a conspiracy. It would simply mean that a jury found reasonable doubt. Much more likely, however, is that a 1964 Dallas jury would have convicted Oswald in about two seconds based on the overwhelming evidence against him. To save his own skin, Oswald might even have plead guilty in return for filling in the historical record relating to the events of the assassination similar to James Earl Ray. After a few years in prison, Oswald would then have cultivated the CTer crowd by hinting at the involvement of others to garner attention and sympathy for himself. So no clarity would have ever come from Oswald himself or a trial.
It's ultimately the evidence that controls these determinations. In the case of the Lincoln assassination, there is clear and overwhelming evidence of a conspiracy. In the JFK assassination, there is no such evidence. Absent something new coming to light, which seems unlikely after nearly six decades, the only reasonable conclusion is that LHO assassinated JFK and there was no conspiracy in the commission of this crime.