Sorry, I'm still confused - any chance you can post a photo of the damaged items?
Typically if the rear wheel hits a curb, you need the rear wheel carrier, which contains the rear wheel hub, brake rotor, and has all 5 suspension links attach to it. This particular part could be borrowed from a 300E, preferably a late one with M104 engine to get the larger dust shield. You'd need to use the 500E brake rotor though.
The axle shaft and differential with gears are usually not damaged. If for any reason you need to replace the axles or differential, NO, the 6-cyl parts are different.
Photo below of the back side of the rear wheel carrier, where the 5 links attach... this is what usually is damaged with a curb hit:
View attachment 92894