Curious why you think Bama has better computer metrics. On Massey's ratings (
Massey Ratings - College Football Rankings), Notre Dame is #7 and Bama #11.
Notre Dame lost to two playoff teams by a total of 4 points, Bama lost to two playoff teams by a total of 23 points plus a non-playoff team by 14. Notre Dame's losses were early in the season, Bama's season finished with a loss.
I get that Bama's SEC schedule was better than Notre Dame's ACC schedule, so they had better wins. But as far as likelihood to win games in the playoff, Notre Dame's profile looks more promising.