I did some research on the issue of the tow hitch cover/cap and goes by different names, same thing. When I googled image of the part number, almost all shows the 6 holes/opening facing the front bumper and not the grilled type cover. It seems to me that the part was made aftermarket. My best guess to find the grilled-typed tow hitch cover/cap is at the junkyards that has the original part in the first place.

tow eye cap
Part Number: 12488001059999
cover tow hook
TOWING BRACKET COVER FLAP
Brand Code
Alternative products (oem numbers)
MERCEDES-BENZ 12488001059999
MERCEDES-BENZ A12488001059999
MERCEDES-BENZ 1248800105