Incomplete repairs suggest that DJIDroneService don't have skilled service technicians, replacing all the screws and checking for any missing is "repair 101"
You should get your original RC back, not one that has been scratched and with loose antenna's which suggest it has been used many times.
A 3 week old unit should be like new and tight in it's operation
Some one at DJIdroneservice took advantage of the situation and swapped out your new RC for their old used unit and rebound the substitute RC to your AC.
A new controller is over $400 usd, so to replace one costs a lot, so it's not a small matter not to get the original one back.
Next time take, date stamped photo's (newspaper date in the background) of all your equipment from all angles before sending it out, also add identifying marks to your equipment.
Maybe Dirkclod should not be recommending them so readily, as they are not DJI recommend or authorised repairers, which will lead to problems if the AC is still under warranty.
Due to their name, a lot of people has mistaken them for a official DJI recommended and or authorised repairer
They probably should be taken off the approved vendor forum list, as this is misleading to other forum members implying they are somehow recommended by this forum
They need to make this right very quickly