So we look at the records of the four teams compared to each other.
Oklahoma: 1-2 [win over TCU, losses to ISU and WVU]
TCU: 1-2 [win over WVU, losses to ISU and OU]
ISU: 2-1 [wins over OU and TCU, loss to WVU]
WVU: 2-1 [wins over ISU and OU, loss to TCU]
Based on this, Oklahoma AND TCU should be eliminated as they have the worst records. This means Iowa State and West Virginia would play for the inaugural Big 12 Title Game.
https://www.smokingmusket.com/2017/...g-12-title-game-wvu-football-oklahoma-sooners