In the Mercedes technical books, there are references to resurfacing rotors, and generally specifications are given as to the minimum thickness allowed. Also given are specifications of the requirements and tolerances for a machine to be able to resurface such rotors.
I've looked into the machines, and it is EXTREMELY costly to obtain one that meets the recommendations listed in the technical manuals. The price for Mercedes rotors is such that it would be difficult to charge labor for resurfacing, charge profit to pay for the equipment, and have it cost less than a new rotor.
Therefore, it is unlikely you will find a shop that has a machine that meets the minimum requirements. So most shops will tell you "oh you just can't do it."
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