Radio theft and swapout at renault

Long story short, i took my car in to get a key encoded and my radio was swapped out with a broken unit at renault centurion and now they want me to pay half the price of the new unit or install a second hand unit into my vehicle. <br> <br> I realized that the radio had been swapped due to these 5 signs<br> <br> 1. Wasn't working properly (Buttons wouldn't work, radio wouldn't display with the car interface)<br> 2. Radio was in a \newer condition"than my radio (Previous owner of my car was a female and her nails scratched the face)<br> 3. Radio Security key is not the one i recognize (They removed the radio and checked what the key was and confirmed it was not of my vehicle)<br> 4. Radio had a cd in that was not mine (Had some R&B house music cd in)<br> 5. Radio had greasy finger marks all over it. (Looks like the radio was retrieved from a junk yard"