From UIL website:
However, the tie can always be broken by determining which band was ranked highest by at least three judges.
In this case, Duncanville was placed highest 2 times, Churchill 1 time and Reagan 2 times. I presume they used this same tie-breaker method to settle the remaining tie between Duncanville and Reagan.
Duncanville - 2,1,1,2,1
Reagan - 1,2,2,1,2
Here you have Duncanville coming out ahead, placing highest 3 times to Reagan's 2.
I guess they started out all over again to settle the 4th place tie between Churchill & Reagan (Churchill with 3 highest, Reagan 2).