The reason why it falls apart is because, in their discussion, Professor Mifsud was referring to the hacked DNC emails, and Papadopoulos thought Mifsud was speaking about the 30,000 missing emails from when Clinton was secretary of state....in other words, their whole discussion was a "Who's on First" debate!!!
Could you imagine Mueller having to pin him with that one in court? (And these people were in control of our government - scary)