Doesn't Bama play a lot of zone?
Couple of thoughts...
I think Dre is your best cover guy. But I believe the poster earlier was correct that he always lines up on the right. I wouldn't try to use him to lock down one receiver the entire game. That being said, when Bama does walk the DBs up into a man I would in fact put Dre on Alshon. I know USCjr has a ton of height at receiver but Jeffries is easily the best on that team. I wouldn't be too keen on putting Milliner on him one-on-one, at least not without Barron over the top for help if he gets burned.
Ultimately, I don't think it is going to be an issue. Read my entire next sentence before flaming me for what I'm about to say. Your secondary is still your weakest link (keep reading!) but that isn't saying much. They look world better than they did to start the season. Getting burnt so badly early in the Arkansas game may well have been what your group needed to wake them up. Receivers do still find space. Even UF receivers were able to get open. Garcia is not a remotely passable QB under pressure. If your front seven can get consistent pressure on him it won't matter what happens in the secondary because Garcia will be good for a pick or two just off of pressure alone. The Ol' Ball Coach will pull some tricks out of his hat. I'm sure he's seen game film and sees ways to exploit the secondary but I don't believe there is a QB on his roster good enough to stand in there against the pass rush and still be able to read the coverage and make accurate throws. If Ryan Mallett is the best the SEC has to offer with regards to big-time QBs, Garcia and Shaw will not stand much of a chance. Their only hope is to get receivers open quickly, hit quick throws and let the receivers try to make a play after the catch. Unfortunately, for that plan of attack to work they'll have to be able to break through your LBs and such--don't see that happening.
This is a big game for USCjr. Gameday is coming to town, nationally televised game at home against the #1 team in the country, the SEC East is theirs to lose at this point. The crowd will be amped. They have a fairly stout defense and it may well be close early but I just don't see them being able to last. Our running game was able to wear them down by the end of the third quarter which allowed McCalebb and Dyer to find running room. I don't think they're going to be able to withstand the physical punishment of Richardson and Ingram. Dyer is a stout, bruising-ish runner, McCalebb is a slasher that does more damage on the outside; two completely different styles between our schools and in this case Bama's will be harder to defend for USCjr.
It isn't impossible to see an upset Saturday but I damn sure would be surprised to see it happen.