Over ten years ago Bell pilot Roy Hopkins flew 609 Ship 1 on an autorotation test flight that proved the aircraft rotors had sufficient energy to safely land the aircraft. In airplane mode the engines were brought to idle and an emergency reconversion to helicopter mode was conducted. Roy then executed an autorotation manuver that reduced aircraft vertical decent to zero and forward speed to near zero. The only thing missing from this test flight being acceptable for certification was it was conducted at altitude and the aircraft never touched the ground.
So what Leonardo is requesting is only simulation of the aircrafts handling qualities as the aircraft touches down. Not if the rotors can arrest the aircrafts decent in autorotation.
Added note. Roy actually pulled to much collective and Ship 1 not only stopped decent by increased altitude before it was reduced to achieve simulated touchdown. Proving the aircraft has rotor energy reserve.