Prong collar will only make a fearful dog more fearful and or toss it into shut down. They are no way to build a relationship built on trust and a fearful dog needs to trust you.
Let me tell you you are not the only one that ever had a hard time finding a trainer been through a few here and just broke down and learned it all myself.
I also lucked out and found a great mentor.
Have a look at clicker solutions and well as truly dog freindly sites as tehy have a list of trainers especailly Truly dog freindly that will not use pinch or prong and will be very helpeful. I had a look and there is a few trainers from postive in Maryland.
Truly Dog Friendly » Truly Dog-Friendly Trainers
So you know mine is a fearful one that will crash and burn under stress and is now turning around with many years of work.
JL