Big 12 tie breakers are 1. Head to head record. 2. Best record against the top teams in Big 12.
So for WVU compared to Texas and TTU all are 9-9. WVU split with both. All 3 are 0-2 to Kansas. Only WVU is 1-1 with Baylor. Hence WVU is seeded higher. The wrench is OU. If OU gets out of its hole against TCU, they'll have the same comference record and the head to head advantage on WVU. I'm not sure what their position is relative to Texas and TTU, which is why it could get muddy. But if the Sooners lose, WVU is guaranteed 3rd seed as far as know.