Would dismissal at 1:00 pm had those children on the road or going to homes where there were no parents? They may have thought the storm was too imminent to send the buses out.
How did the much larger OKC school district manage to safely dismiss their students? Perhaps neighboring districts should ask for their plan. They dismissed two and a half hours before the storm struck, so there was ample time.
Sending kids to a basement with overhead water pipes was not a safe plan, obviously.