I would be shocked beyond belief if they went with SMU over Bama.
In the rankings, they are 8th and Alabama is 11th. Miami last week was 6th and lost on the road to a 9-3 Syracuse team that is ranked 22nd and they dropped all the way to 12th. The only difference here is this was the conference championship game.
But to your point, how does a win over Georgia offset 2 losses vs 6-6 teams (1 of them by 3 Touchdowns)? If we were comparing teams with equal losses, then yes, they should be in. But 3 losses vs 2 and not even in your conference championship game which would be another chance at losing a 4th game (a game they would be a TD underdog in).
Alabama PROBABLY would beat SMU on a neutral field. But they probably would beat them on a neutral field if they were 7-5. At some point, THE GAMES HAVE TO MATTER!!! Otherwise, why even have a regular season?