Not sure why you said Warren did take a stand against it:
Big Ten Commissioner Kevin Warren Releases Statement on Failed CFP Expansion
Few outside the SEC and Big 12 wanted an expanded playoff with ESPN controlling the TV rights. If ESPN won the rights, it meant more SEC teams in the expanded playoff at the expense of other power conferences. Why would the other conferences leave more money on the table while losing a seat at the playoff table?
It's wishful to think ESPN was going to share an early-round game with another network. ESPN had no intention of sharing the CFP with other networks. The exclusive window for ESPN to negotiate was to lock up the CFP for good and block any network or conference that did not bow to them. If you remember anything, ESPN is all about self and will destroy anything that stands its way. Just ask Big East football how ESPN didn't want to pay for the product after the conference showed it was a peer of the other power conferences at the time. Instead, ESPN advised the ACC on how to kill off the league and advance the cause for both. The previous Big 12 conference sent letters to ESPN to stop interfering with the conference's survival as ESPN.
I might be in the minority, but SEC is now a step behind the B1G. What the B1G did with stopping CFP from being exclusively on ESPN, to USC & UCLA joining, to the most extensive media deal across multiple platforms is checkmate to other conferences hoping to stay in the game. The SEC is concerned in a big way. LSU HC mentioned the SEC commish discussed the possibility of an SEC playoff since ESPN is losing its grip on the CFP and will have limited influence on the playoff selection committee under the new deal.