Thanks to the restructuring of the contract two years ago, it would have been very difficult, logistically, anyway.
Romo signed a six-year, $67.5 million contract extension in October 2007, and there was still $24,999,835 (about 37 percent of the deal) to be accounted for on the Cowboys' salary cap going into the 2013 league year, the final year of the contract. Romo's cap number for 2013 is $16,818,835, and the $8.181 million left over in prorated money is built into three voidable years, tacked on to the contract as an accounting measure during the 2011 restructuring.
Because the deal voids, as Rapoport reported, after the end of the 2014 franchise-tag period, it's impossible for the Cowboys to tag Romo. But even if they could, it would create an untenable situation on their salary cap. Romo's tag number would be, at a minimum, $20,182,602, and the $8.181 million in prorated money would accelerate on to the 2014 salary cap as soon as the old deal voided, landing Romo's cap number for 2014 at between $28 million and $29 million.