Reminds me of that Sci-Fi comedy movie "Galaxy Quest". On an alien planet, the commander tells his people to give out a warning call if the aliens attack. One guy says I'll yell "Caw, caw, caw!". Commander says "Are you a child? We have radios!". When the aliens attack, the guy on watch comes out screaming "Caw, caw, caw!".
What happened at the shooting disaster was an amateur sh*tshow by the SS. If they practiced before the event, it did not go well in reality.
I am sure the cops and SS folks who saw the shooter climb the roof notifying command and control.
The conspirators were command and control.
That is why nobody on stage got the word.
This was not incompetence.
This was premeditated attempted murder by moles in the Secret Service.