"VII-X" sounds like it would ruin both games. Unless they add into the story that some point there were two developing worlds that split apart, and one became VII and the other became X. So you could reason that since there are still theoretical "bonds" between the two worlds, Don Corneo is Shinra's brother in X, and therefore Shinra funds Corneo's actions in VII because of his love for his brother in the other world. Also, the game could then be called "VII-X Split"