I have no doubt that Chuck Berry was the real father of Rock - but Elvis was the guy who opened up Rock to the world from its limited exposure before. He was a crooner - later - but his first popular recordings were the real thing.
Boogie Woogie, Western Swing, Jump Blues and Hillbilly Boogie were all being performed by artists such as Louis Jordan, Bob Wills and the Maddox Brothers and Rose years before Elvis, Chuck Berry, Little Richard or Bill Haley. They were closer to being the Fathers than the 1950’s performers.