This is who they have played in conference:

USF 6-5
UAB 3-8
Rice 3-8
N Texas 5-6
Char 4-7
Temple 3-8
Navy 7-3

31-45 combined record for in-conference opponents. Likely the weakest in conference schedule in the AAC. The Big 12 has only one team that is 3-8 and that one team beat Arkansas.

Tulane is 2-2 out of conference, with losses to K State (at home) and Oklahoma.

BYU's combined conference opponents are 44-44. BYU is undefeated out of conference with a win over SMU. With Tulane's schedule, BYU is no worse than 10-1, having beaten K State with maybe a loss at Oklahoma, but I bet we get that one on the road. There is no metric that should put Tulane ahead of BYU in these rankings.