This whole thing was timed in order to make it come about during the impeachment hearings. Imagine trying to get people to focus on impeachment hearings when the media is, instead, talking about corona.
So, by not calling witnesses, the impeachment nonsense drops and now Corona is front and center in all its absurdity.
Do you think the President could just stand up and tell people the truth about what is going on? Even if all documents were to be declassified - every single thing, fully intact with no redactions - people wouldn't read it. The media would read through it and package excerpts from it to paint the picture they want.
Let the press invalidate themselves.