i dont know, greatest cast ever seems a bit far out, is he only counting video games? if so, probably. but if he includes movies, then im sure i can find a few with even better casting.
however, a good cast does not guarantee that the game will be good. first of all, that is just three characters, what about all the others? second, what about a good story? third, gameplay. fourth, graphics. fifth, for me anyway, replay-ability. (i prefer games that you can play over and over again. i got oblivion when it first came out and only stopped playing it last year)