So he is too afraid to give this statement to Congress under oath?
Mueller, as all liars, knows that it is not a crime to lie to the public. The Clintons were champions at this. The media will be happy to quote Mueller's lies over and over until the LIV's of this country believe his lies.
Somehow, on the other hand, things that Trump said at his rallies, even when they were clearly a joke, were ok to be included in the Russia investigation. Of course there was no crime so that entire investigation was Bizarro land.