So the only way to tell if it is still alive is to trim off a side branch a couple inches at a time............if it is still alive you will start to see green inside a cut part. Fruit trees are not happy when 2 heavy frost hit it. The center piece still might be alive. I would leave it alone and see what happens in the spring. By early spring you might only see some prebudding on lower inner branches. By May you should know. If you so see prebuds starting and you are warned of frost. you could use a night cover using a long pole to cover it and tie it down and you take it off when the temps are over 32. We had the same problem 4 years in a row. This is the first year that any of our trees had fruit....we live in NE PA