have'nt you looked at the engine mounts as i had suggested? The engine will still be moved about even if not being used when rolling down the road. My car had literally everything replaced that could have been worn out suspension wise on my old mk4 then they finally out of the off chance changed the engine mount and that was what was causing the noise.

i never noticed that one as i never bothered to look on that side as the noise was from the n/s