1.). There shouldn’t even be a trial. This whole process makes a mockery out of a judicial process. In a court of law what he said doesn’t event justify charges of inciting a riot.
2.) If there is a trial, Trump should be able to present every case of fraud. He should take 6 months doing so, tying up the Senate by filabusting his defense. After all, they are trying to impeach him for saying to his supporters the election was rigged and therefore they should riot. This is his chance to prove to the American public in a forum the media has to broadcast - that the election was actually rigged.