3. Ball St beats BG, BG beats Miami
In this case Miami, Ohio, BG, and Buffalo are all 6-2
Miami beat Ohio, but lost to BG. Ohio lost to Miami, but beat Buffalo. BG beat Miami, and didn't play the others. Buffalo lost to Ohio, but didn't play the others. Not sure how this works, but it seems Buffalo would be out, and the game would be two of the three (Miami, BG, Ohio). I would guess that it would be Miami-BG in this situation, since BG would have the tiebreaker over Miami, while Miami would have the tiebreaker over Ohio.
MACC Game= Miami 6-2 versus BG 6-2
I'm not sure if I understand these tiebreakers correctly, but I think this could be a chance for Buffalo to go. First tiebreaker for a multi-team tie is combined head-to-head win percentage among the tied teams if all tied teams are common opponents. They would not be all common opponents in this case, so it does not apply. BG didn't play Ohio or Buffalo, and Miami didn't play Buffalo either. So the second tiebreaker wouldn't apply either: If all the tied teams are not common opponents, the tied team that defeated each of the other tied teams advances.
So then the third tiebreaker: Win percentage versus all common opponents. There are three opponents that all four tied teams played: Toledo, Ball State and Kent State. In this scenario where all four teams end up 6-2, the team records against those three common opponents would be: Buffalo 3-0 and the other three teams 2-1 (Ohio and BG would have losses to Ball State, while Miami has the loss to Toledo.) So I think that advances Buffalo to the title game.
From there, it's not clear. To determine the second team, do you start over with the three remaining teams at the top of the tiebreakers or continue through the tiebreakers? I think typically once one or more teams is eliminated, you start over, but it doesn't say that. But if you do start over, it would come down to common opponents again, since Ohio and BG didn't play each other, and in this scenario, Miami split with the two teams.
So common opponents for all three of Ohio, BG and Miami are the same teams as before (all 2-1) plus Central Michigan, which all three teams beat, so either way you geto to the next tiebreaker, win percentage vs. common opponents based on order of finish. Toledo is probably the highest finishing team, assuming it beats Akron, and if that's the case Miami would be eliminated by its loss to Toledo whereas the other two teams won. So then you have a two-team tiebreaker between BG and Ohio, and that would come down to win percentage vs. common opponents, which BG would win because of their win against Miami. So if I have this right, it would be BG vs. Buffalo in a four-way tie, but I might not be applying something correctly.