THEN DO IT!

Trump has the power to get all the evidence he needs.  He can read all the EOs, he can order the FBI and CIA to tell him about any wiretaps, he can do whatever he wants.

If everything you say is true then he needs to do this.  Surely even you realize the ridicule will continue until he either takes back his comments or he produces evidence.  There is NO EXCUSE not to produce evidence since he has access to everything now.