I'm sure it's mentioned in Moon Shot[1]. Most books about the space race mention it. Houston was just one of several proposed locations which met NASA's official specifications for a mission control site.
One of those specifications was the minimum distance between mission control and the launch site. That specification was revised upward so that it just barely excluded the then-leading site after Rice University agreed to donate the land. It doesn't take a Von Braun to figure out what happened.