Update 6-28
I received a call from the franchise owner after receiving my certified letter who was very apologetic and refunded all of our money. He understood and agreed with the fact that we were upset because we never received a return call from the supervisor after so many days and so many of our attempts to contact him and was sorry the car never got fixed.
It's such a shame that the supervisor disrespected us like he did and the mechanics couldn't fix the issue. We've been customer of theirs for years and have always had good service. However, we will no longer patronize or recommend their shop, especially with the supervisor they have now.