Thing is, people in all professions receive multiple career accolades all the time--often within short order. I do not agree with any need to insert any specific time buffer between such achievements. Everyone associated with sports will acknowledge Johnson as a Hall of Famer. Likewise, anyone associated with the Cowboys will recognize Johnson as a Ring of Honor member when he is inducted. Alive or dead.
Neither honor will take away the other. In fact, I would argue both will enhance the other.
Johnson himself asked when will it happen. Even the actual person, who would receive the honor, does not understand the necessity to wait. Why should anyone else?