I don't dispute this, but why isn't his name in the record books?
After the war, Welch returned to flight testing; this time in the F-100 Super Sabre, with Yeager flying the chase plane. Welch became the first man to break the sound barrier in level flight with this type of aircraft on May 25, 1953.
He is also in the books for being a recipient of the Distinguished Service Cross (and Medal of Honor nominee) for his heroics along with Ken Taylor on Dec 7, 1941.
His history is well known in the flying community, not so much to the general public.