Probably because the actual 3rd facelift of the 3GS (with the different wheels, clear tail lights, veeery chromey front grille, lack of cassette tape & so on) has a different part number for the pop-out buttons assembly. AFAIK, it's extremely rare to find such a car, let alone wrecked. Wouldn't lose much sleep over this.
EDIT:
GS460 seems to have had this from the get-go. Weird.