Unless a deal is reached that is satisfactory to the remaining 8 schools, there is every reason to follow-through with a tort lawsuit against ESPN/SEC/OU/UT. At the very least, the threat of discovery seems significant for those parties when considering their contractual obligations. ESPN/UT/OU seemingly wanted this move to happen quickly and for the BigXII to get swept away in the chaos of a "sinking ship." Threat of litigation may also slow down the SEC's vote on OU/UT invitations like Baylor's threat of legal action did for A&M last go-round.
The difference between last time with A&M and this time with OU/UT is that Baylor didn't suffer damages when A&M left because ESPN gave the conference the same money despite A&M leaving. That was the primary reason Baylor's attorneys backed off and didn't file anything. All the same, the SEC postponed their invitation for A&M until that was resolved. With OU/UT leaving the way they are under the current circumstances, the potential damages are massive and bad faith actions taken by ESPN/OU/UT/SEC could be a factor in potential legal proceedings. I will be mighty surprised if the SEC doesn't postpone the vote for OU/UT (currently scheduled for today) at least until there is more clarity around the legal shenanigans here.