There are enough aspects to this incident to choke a horse.
One can go through the mistakes made and indeed the entire scenario from the beginning and find the entire thing filled from top to bottom with factors that should never have happened.
The ultimate answer to this is that literally EVERYTHING was wrong from beginning to end.
The incident is literally filled with "what not to do".
Were I to be lecturing on this I would not only be discussing the incidentals but as well the system that allows incidents such as this one to develop and take place.
There is much to be learned here and it's easy to get bogged down in specific details. The danger there is in possibly losing the "big picture".
Dudley Henriques