The ParkMe feature doesn't have any effect on what the ATC will do. The ATC will still function as it always had, which means you can't freely decide where to park.
The ParkMe feature works separately so, regardless of what the ATC has decided, you can freely select any parking. It can be the same parking the ATC gave you, or an entirely different one, that's your choice. The ParkMe will then activate a docking system in that parking, and give you an evaluation of the parking accuracy at the end.