"instead of letting the letter go through proper channels"
You missed the BIG issue....the transcript would never get out as the WH established a separate computer system to store transcripts damaging to Trump. Think Watergate...
"White House lawyers directed White House officials to remove the electronic transcript of the Zelensky call from the computer system where such transcripts normally are stored. That transcript then was loaded into a “separate electronic system” that is otherwise used to store and handle classified information of an especially sensitive nature. “One White House official described this act as an abuse of this electronic system because the call did not contain anything remotely sensitive from a national security perspective.”"