[Theoria]

I'm not saying anybody threw or shot anyone. But, if all the damaged trains passed thru the same corridor, it simply could have been debris or a similar obstacle that they all came across. Nothing needs to be thrown or shot, the train itself is creating the force, any stationary obstacle is bad enough.

[MeshugeMikey]

would a stationary obstacle have raised a red flag....and there have been communication from the first two trains that “collided” with it or parts of it?

no mentions been made of anyone seeing a stationary object on or near any tracks that I know of.