You need to get a second opinion from the best independent shop you can find. This is all very fishy. It doesn't cost much to buy a compression tester - maybe $20 at Harbor Freight, and it isn't hard to do. It's the one way to actually know whether you have a compression problem. I'll bet you don't. Also, you gotta tell us how many miles on the car - 50k or 250k makes a difference.