If LSU wins and OSU and Clemson were to lose somehow, that would make things interesting. You would have Oklahoma likely get in with only 1 loss and by virtue of winning their CCG. Then OSU and Clemson also only have 1 loss, but OSU has actually beaten some good teams this year. Clemson would not have really beaten anyone of significant in that scenario, so I could see OSU getting a bid still with Clemson fighting Wisconsin or another 2-loss team.
Again this is an unlikely scenario as I don't see OSU losing and I doubt Clemson will lose either.