Maybe the reporter got it wrong? Always a first time.

UPDATE
He modified his story to the following:
Anderson also couldn’t catch any breaks in its victories as a 26-20 overtime victory proved to be its undoing. In that game, the Trojans scored on the overtime session’s second possession and thus didn’t need to kick the extra point… but three weeks later, that extra point would have given them the edge over Austin High in the threeway tiebreaker between Del Valle, Anderson and Austin High that decided the district’s final two playoff spots. I asked a co-worker who is associated with the Texas Association of Sports Officials and he told me that there is an NCAA-approved rule that automatically ends overtime football games in similar scenarios to the Anderson/Del Valle one but he was unsure if the UIL, which follows NCAA rules in football, has an exception to that rule since a lot of tiebreakers factor in points scored. I have a call out to the UIL so we’ll try to update you on this story later.
UPDATE: The UIL allows an exception to the NCAA overtime rules for districts that use positive points tiebreakers (like District 15-5A). But the schools’ coaches must inform the officials before the game that they play in a positive points district