OhGoodness?
really?
The boy initially reported the attack. And he would have been asked when it happened. So they would have known it happened at approx. 8am, 1pm, 3.30pm etc. whenever he claimed it happened.
And the cctv should have been quickly viewed. ASAP. For around that time.
Other students may have needed to be asked.
None of this takes THAT long.
Or, it would have become apparent very quickly, that something didn't add up.
And the times that Op's ds claimed to be in a different part of the school, or walking along the maths corridor, or whtever else he claimed, could have also quickly been viewed.
And whilst they might not have been able to categorically say 100% what had happened at this stage.
It would have been clear to anyone that certain bits were questionable.
And you don't think that Me, or most of us, would have been able to manage that?
I expect such from any reasonable school.
It does all seem to have taken far too long.