Meineke Car Care Center

At July 27/2015 while I was driving my car near to my home I found the sign for the Econo Lube N Tune Meineke mechanic Saying that they fix domestic and foreign cars I came down and asked the technician who came out if they can fix my car (Mercedes Benz) He replied yes and they have the computer able to make diagnosis for this types of cars and his mechanic worked with the Mercedes dealer for five years, He told the expanses it will be 120$ and it will take about two hours for diagnosis.
When I came back He told me there is a lot of problems came as a diagnosis and it will cost a lot and he advised by it's a time to get new car, I tried to understand what is the parts exactly needed to replaced and how many hours needed for labor ? he was not able to come exactly by a correct answers for those questions and came with speculation about the parts and told when you get the parts, I'll give discount for the labor and charged me 120$ for diagnosis.
Because I was not convinced about the diagnosis and because the parts of this cars is very expensive I decided to take the car for the dealer for further evaluation, and in the Dealer it was the real surprise waiting for me after few hours of trying to make diagnosis they called me and told me there is no computer able to read the car because there are wires and hoses missed and it has to be replaced first for 490$ so the computer can read it.
When I explained for them the car is already diagnosed in another workshop few days ago? the answer it was that It is impossible for any computer to read this car as it is and they returned the car for me after all their work charge free.
When I went back to ask this Technician in Econo Lube about the case and explained what happened in the dealer he came with very weird answer he told me may be their computer in the dealer is not advanced enough or their technicians they are not professional enough.
when I asked for a phone number for a supervisor he told me he will give my number for him and let him call me.
When I called next day to ask why the supervisor didn't call me he replied he gave him my number and he will call .
Now after three days I didn't receive any call yet and I am not expecting to receive any call.