Way back around 2011-12, there was a settlement offer from the Os that started low (around $40-50 million) but escalated to 100 million by end of 20 years.
The Nats should have obviously taken that deal. On the surface it might have sounded like a bad deal with big tv contracts being signed all over the place, but it was easy to see RSNs were going to be a bubble and I'd guess there was some short sighted greed mixed in with some pride and stubborness that kept them from taking that.
They could still easily work out a settlement that just paid the Nats something like 40% of the revenue with no ownership stake and everyone could move on.
Freeing themselves from MASN without much backpay would be a bit of a disaster for the Nats. There is 100s of millions of unsettled money from the past decade they should get, and if they get out of MASN, they have nothing but Leonsis's channel left to go to. It's probably worth something to Leonsis, but it would be tough for him to monetize adding the Nats to the point where they would be willing to pay more than 20-30 million and that might be a stretch.
The ufortunate truth is, at least for the short/mid term, MASN brings in exponentionally more revenue with carriage agreements in place, than anywhere else the Nats could go.