2013 ML350 bad shock absorber

The vehicle has less than 52k miles. Does this even sound right? Not sure what all is involved to replace, but I believe the left rear shock P/N is 1663200930 , which retails for $571.55.
https://mercedespartscenter.com/part...iagram=5774845
Should I just have the shock replaced by an indy, or does it require Mercedes software equipment to service a vehicle with Airmatic?
There were other issues found too but covered by ELW:
ENGINE MOUNTS (ENGIE AND TRANS MOUNTS BAD): $1,223.77
TRANSMISSION MUNT (ENGIE AND TRANS MOUNTS - BAD): $120.00
CHARCOAL CANISTER AND SHUT-OFF VALVE (CHARCOAL CANISTER AND VALVE FAULTY LEAKING): $729.92


