Trump isn’t complaining. Trump is getting his view out there.
That report only shows one side. There are always two sides to every story.
Why did Trump allow McGahn to testify, knowing that his testimony would be so damaging to Trump?
The answer is even more intriguing. I believe the purpose of this was to get this particular piece of information into the public domain ... because it's actually NOT damaging to Trump.
President Trump had the legal authority to fire Mueller at any time. Period. It may have been a terrible move politically, but there would have been nothing illegal about it.
A DOJ official operates as an executive branch officer, and ultimately answers only to the President. This is established under the U.S. Constitution, and under the enabling legislation for the DOJ. One of the unique features of our form of government is that we have an independent chief executive, and in recent decades one of the strongest proponents of this concept has been a guy named William Barr.
Just something for y'all to think about ...