I'm ONLY talking about the ONE game in question. The rest is irrelevant.
IF the B12 plays a 9th conference game, the MOST they can have is SIX games (given a 12 team league).
IF the B12 only plays 8 conference games, using what would have been the 9th as a OOC game, the conference would have as FEW as SIX home games and as MANY as TWELVE home games.
See how they don't lose ANY inventory playing other P5 teams? They also nearly guarantee worse records overall playing 9 conference games vs 8 games.
Do the CAPS help?