dead car, no electronics, jump needed to start car

I took it to a Ford Service for repair. They said no problem found and the battery was good. However after signing the paper work they went get my car with of those devices to jump a car. I followed the guy and he went to my car and used it to jump my car. I went back in to talk to the service advisor and told me to take my car anyway because they didn't have a fix for this issue right now.