But that is exactly when it would hurt the investment firm the most. The large upfront payout ( $2.5 B ) means it's the next media rights deal when they get the ROI. Not having Michigan in that deal hurts them. Hence the reason they've said it's a no go if all 18 Big 10 teams don't say yes.
Look at Notre Dame, their current media deal is paying them about $ 50 Million a year. Plus the $ 17 Million they get for that BS arrangement with the ACC. That's roughly the same as the top tier Big 10 teams. They get to make themselves an easy path to the CFP with how they schedule. For example, look at this year. They played 3 real games this year ( Miami, Texas A&M and USC ) and lost 2 of them ( Miami and A&M ) only beating USC. Currently they are ( unjustifiably ) sitting pretty in terms of getting in the playoff.
Michigan could easily do the same and just make a similar BS type agreement with say the Big 12 for 5 games. It would give them an easier path to the CFP and would help keep the brand high up the list of desired media deals.