Crash during Orc Hunt Mission

I was playing the imperium campaign, where you need to defeat the Orcs while the space whales come in and distract you.
Somewhere during the middle of the mission the game crashes with the error message "fatal error", there is no fixed point when the game crashes but I believe it has something to do with the Orc Rock fortress dieing, two times catapulting itself over half the screen and disappearing, one time it just died from focus fire.
Not sure if that causes the crash but the game generally breaks around the time I kill it, which is the only common nominator I could find.

I am also having crashes at during the Ork Hunt mission. At the end of the mission I get an UE Fatal Error. It appears to similar to what is happening to some when finishing abbadon's chosen.