We don't have any way of knowing that from the evidence given.
True. Does that mean we can't definitively say that C dies either?
If we only assume 3 things; that E is pushing the Boulder, each boulder is made out of the same material based on its shading, nobody can move; A won't get touched. B will be trapt. C will be severely injured or die D will live due to the gap in the moving Boulder. E will live because he pushed it.