From the Orange Bowl Conference Tie Ins rule:
“… Also, should a highest-ranked team create a rematch with the ACC team, the Orange Bowl has the option of passing over that team for the next-highest ranked team among the Big10, SEC, and Norte Dame..”
While Clemson and Ohio State didn’t play this year, or last year, the Clemson vs Ohio State matchup was played the two prior years in the CFB. It’s still a matchup that viewers and attendees may be apathetic to. This wouldn’t technically be a rematch.. but if Clemson wins the ACC then it at least gives the Orange Bowl a little bit of a leg to stand on if they don’t want to accept Ohio State. Not sure it’s enough though. Depends on how much wiggle room they would have and if the Orange Bowl even cares.