Someone shared a video of a helicopter with tied down blades being hit with similar munitions, and the rotor blades do indeed stay fixed in place.

I also wonder how the smoke is supposed to appear underneath the rotors if they're painted on the ground. And there also appears to be a parallax effect with the ground, also impossible for a painting.

It could still be a decoy (eg out of wood or other materials) but it really doesn't look painted to me at least.