According to the TSSAA website Bradley Central was 5-5 and McMinn County was 4-6. Even though McMinn was 3-3 in district and Bradley was 2-4 overall wins is the first thing that determines the wild card teams.
Once the playoff teams are determined the teams are placed in the 4 quads from east to west (the 4 teams furthest east in quad 1, etc.).Although I don't think many know how they determine how the teams from the midstate are placed in the bracket. I would much rather the bracket be split into halves seeded 1-16 instead of quads seeded 1-8. It would create more travel for some teams but it would prevent the better teams from meeting in the 2nd round.
I don't know how true this is but I have heard that there is overwhelming support from the coaches to abandon this system and go back to the old system.