Jesus, your wokedness is resounding in it's breathtaking ability to ignore reality. The transcript is all they need for Impeachment. What do you want to investigate? If Trump has a doppelganger?
And of course they will investigate - wouldn't it be neat if the Drumpf Administration provided the information they were legally obligated to do so (the ICIG Whistleblower Report)? You shrilling "we don't know" is because Trump broke the law already by not providing the information.