If ND & Clemson make the semi-final games then the #3 team in the ACC team will be an auto bid in the Orange bowl. That would be whether it is Miami losing to UNC or not. They do not have to be top 12, etc.

What we would need most is Miami to lose and have them and UNC out of the top 12 and ND or Clemson drop out of the top 4 and then they be the one that goes to the Orange bowl. (which you detailed - but not why)

I'd also point out that the other half of the Orange is the highest ranked available non-champ from the B1G or SEC. With Florida and TxA&M at 5/6 they become that auto bid in that game vs them being one of the at-large and basically the other then becomes an at-large.