I think the elevator is simply not strong enough for the loads. They want it extremely light which makes it delicate. Flying wires might help for the horizontal stabilizer but not the elevator itself. The simple fact that this plane had the same problem with two separate elevators on two first flights implies a design flaw. I could see this happening after some wear and tear or with severe manuevers or high speed. It failed on extremely cautious first flight at very low speeds. I didn't even get a chance to try a 3D maneuver, this was simply a split S at a throttle setting that barely turned on the motor.