Media companies have no say in the GOR's. The GOR's are between the schools and the conference (and by extension all the other conference schools).
They basically say if program wants to leave, the rights (and therefore the money) for their media revert to the conference (and its remaining schools).
So basically, say Clemson wanted to leave the conference, they are free to pay the exit fee (which is 3X the operating revenue of of the conference - currently about $105MM) and could join whatever conference they want. But, they (and the new conference) lose any rights to their media (and therefore that money) until the end of the GOR. So that would mean through 2036, any game Clemson played, the money from the TV contract would go to the ACC (and its remaining schools). Clemson and its new conference home would get $0.
Also, if the ACC GOR is like the B12 GOR (which is highly likely) there is also a piece that any program that wants to leave the conference becomes what is known as an 'interested party' and loses their voting rights on any conference decisions (such as a dissolution vote). So you can't just try to break out of the GOR by simply getting a bunch of programs to try and leave. All those programs would lose their voting rights and the ones who did not break away would be the only ones who would get to vote.
GOR's were largely created for stabilization reasons and have been quite successful in that regard. No program has attempted to leave a P5 conference for another P5 conference until their GOR expired.
ESPN has no reason to see the ACC raided and fall apart, and frankly has multiple reasons for it to stay together. The ACC provides ESPN with more content than any other conference. With ESPN losing its share of the B10 rights, it now has more programming space to fill. not less. Also, ACC Content is cheaper than SEC Content for them, so why would they want a program to go from the ACC to the SEC. That is a negative for ESPN. ACC is also an in to programming with ND, which is beneficial to ESPN.