In point number 3, you state that one of the trains caused the accident, whereas the cause of the accident is not yet known and could be for example an issue in the rails themselves.
The way I looked at it is that the first train derailing wasn't a big issue, I don't think it caused any injuries. What was really catastrophic was the impact with the second train.
https://www.abc.es/espana/andalucia/cordoba/via-l10717-salto...