The running, I can understand a bit; explosion happened distracting them, they assumed when he talked was his return time, and the area was too damaged to retest. The throwing though, completely their fault; not only were they not watching him, and unable to locate where/how he disposed of the ball, they should have still given him a new ball to throw.
Surely they'll claim he used physical force to destroy the magic tester as an excuse to fail him, even though according to the incompetent tester he has no physical power.