I've stated the same point @.@
You can PM BeeAre about it. I already have, some time ago.
All the world scientists knew about it. They were holding a conference under the event at the school. I would find the page for you, but linking stuff from my phone is irritating. Also, the KND would've seen the bomb.
The assumption that the KND only fight adults is also false. They have enemies of all ages. Not knowing who Bell is, they would easily assume that she maybe working for adults, like many other kids have before. ie: The Delightful Children
The add in a cloaking field would contradict a lot from the original series actually. Do you remember why they have a moon base in the first place? In their history, it was set as a haven away from adults, that all adults once knew of.
Again, there were more events besides the current. Their absence at a science convention and meeting about the moon is still a problem.
The absence of heroes is due to BeeAre not wanting to include them, the exact same as the KND. If the heroes were involved, then extensive additions to the comics dynamic and culture would be needed to integrate them. The same reason KND is not involved.
Dexter's show didn't involve extensive plot lines and a long history. Writing out the things the KND were capable of would also ruin canon plot lines and history.
An extensive explanation would be needed. I've offered my own to BeeAre, but I don't believe he cares much for the idea. You're trying to over simplify their addition without any consequences, unfortunately, you won't succeed.