If OSU can only play 1 more game this year due to COVID and gets to 5-0 they will not be able to play in the CHAMP game, and I doubt they will be able to play in the playoffs. Now, if they are able to schedule the 6th game and play it on CHAMP week and get to 6-0 then it does increase their chances.

But then the Committee runs into a tough situation.

If Clemson beats ND in the ACC Champ Game, then you will have two ACC teams at ND (10-1) Clemson (10-1).
If Alabama closes out they would face either TXA&M or Florida in the SEC Champ game.
Alabama wins they will be 10-0, if they lose 9-1
Florida or TX&M win out and either were to lose to Bama they would be 9-2 if they win 10-1

I don't see the Committee taking 9-2 BIG12 Champ Iowa State over a 9-2 SEC Team, definitely not a 10-1 SEC team but I could be wrong. A 9-2 Oklahoma BIG12 Champ might have a better shot, and honestly would be the BIG12 only shot IMO.

ACC won't get a 3rd team into the Playoffs.
The PAC shot themselves in the foot and they won't get a 6-0 USC or Washington team in over a 6-0 Ohio State.

Here is the outlier that could kill OSU shot altogether.

If Indiana were to close out the season by beating #16 Wisconsin and then beating Purdue to get to 7-1 then win the BIG10 Champ game against whoever, that would put them at 8-1. Indiana at 8-1, with the BIG10 Championship, would take a 5-0 or even 6-0 OSU spot in the playoffs (even though OSU won the head to head match with Indiana barely). If the Committee did take OSU over Indiana, it would cause a major raucous around the College Football Landscape IMO.

I don't include Cincy as the Committee will never allow that to happen.

OSU has an uphill battle now that they are limited in games they can play.

Here is how I think it will play out by years end for the CFP:
Alabama
Clemson
Notre Dame
Either: Florida/TX&M/Indiana and OSU for the 4th spot.

Still, lots of Football to be played, and lots of COVID to prevent it and also the Random CFP Committee as well. Take this prediction for what it is worth, 2020 has indeed been a crazy one.