Hello,
I just found a glitch on the second bomb site where you actually have to blow up the train cart itself. On the defending area there is a turret looking directing from the back of the train cart that glitches. What happens when you mount the turret itself, it shows that I cannot shoot nor aim down the barrel of the turret as well as classifying you as dead ultimately not allowing you to do anything.
Here is an image showing that eventually when you do detach from the turret you cannot move anywhere but upwards into the sky.