It happened for 2016 Rosebowl. Iowa was 2015 championship loser.
Yes, but Iowa WAS the highest ranked Big Ten team outside the CFP selections that year. I'm talking about where the champ game loser is NOT the highest ranked Big Ten team outside the CFP selections, but then the Rose Bowl would select them anyway.
That would be our most likely path. We'd play Ohio State in this year's championship game, lose to them, and end up ranked lower than other East teams. Would the Rose Bowl still take us?
Here have been the scenarios since 2014:
2014 - N/A because Rose was a CFP semi-final game
2015 - MSU beats Iowa in the CG - final CFP rankings: MSU #3, Iowa #5, Ohio St #7 - Rose selects Iowa to play #6 Stanford
2016 - PSU beats Wisc in the CG - final CFP rankings: OSU #3, PSU #5, Mich #6, Wisc #8 - Rose selects PSU to play #9 USC
2017 - N/A because Rose was a CFP semi-final game
2018 - OSU beats NW in the CG - final CFP rankings: OSU #6, Mich #7, PSU #12, NW #22 - Rose selects OSU to play #9 Washington
So like you had said before, my scenario hasn't gotten to play out yet fully. Some interesting circumstances have led to that, as well.