It never ceases to amaze me how people take a diagnostic problem to a Midas. They obviously don't have a clue, and I wouldn't expect them to.
They would be lucky to understand the refrigeration system let alone a manufacturer specific problem , let alone a grey market manufacturer specific situation.
This kind of work needs exact answers not guesses. If I thought they had a chance of dealing with the car I'd avise telling them they gave you no value and to straighten it out. But, hopefully you will learn a lesson. The only thing cheaper than a true professional is DIY (and thats not true always).
You can find true professionals at dealers and many independents. Any true professional trapped at a franchise auto repair facility deserves my pitty.
Bosch Master, ASE Master, L1
33 years MB technician