This is a thought only, and has to do solely with reports of little damage to the main rotor blades in this accident:
If one pulls "early' on an autorotation, and ends up -- lo and behold -- above desired spot with a bit of extra altitude, would not the blades be mostly out of inertia as one makes contact with whatever is below one at the bottom?
That is one way to explain general lack of damage to main rotor blades, I think.
Please correct me if I am making a meal of that thought.
EDIT:
Question for clarification: is EC135 high inertia rotor system or low inertia?