I don't know how all of the neutral site games work, but using the Texas-UCLA game played at the Dallas Cowboys stadium in Arlington, TX a few years ago-- that was actually a UCLA home game, that they just chose to host in Texas rather than in the Rose Bowl. So the PAC television contracts covered the game, and Jerry Jones paid them some amount of money from the gate/parking/concessions to entice them to give up a home game and play it in Texas instead. If I were a UCLA season ticket holder I'd probably be pretty hacked off at that arrangement, but this is the world we live in I suppose.
For TX-OU, the profits from gate/concessions/etc. are split half-and-half, the city of Dallas kicks in additional payments to each team, and obviously since it's an in-conference game, the B12 television contracts govern its broadcast.