(Please correct me if I am wrong)
BYU, KSU, ISU, and CU all play Kansas.
For any tiebreaker amongst 3 or 4 of those teams, we haven't all played each other so H2H doesn't count.
The next tiebreaker, according the rules, for a multi-team tie is: "The records of the three (or more) tied teams will be compared based on winning percentage against all common conference opponents played by all other teams involved in the tie."
If we lose to Kansas, and two other one-loss teams have beaten Kansas, we are toast and out of luck.
If we beat Kansas, then either we are undefeated, or even if we have one-loss we would advance over teams that lost to Kansas.
Additionally, the next tie-breaker is "Record of the three (or more) tied teams against the next highest placed common opponent in the standings (based on the record in all games played within the conference), proceeding through the standings. When arriving at another group of tied teams while comparing records, use each team’s win percentage against the collective tied teams as a group (prior to that group’s own tie-breaking procedure) rather than the performance against individual tied teams."
So as there is no other common opponent other than Kansas, it would go to overall opponent W/L, where KSU advances. Then, according to the rules, the tiebreaker resets with the remaining teams, where we would beat ISU or CU based on the above tiebreaker having beaten KSU. (If ISU beats KSU then KSU isn't in the tiebreaker anyway so this assumes KSU wins)