Hello Japanese gardeners

We purchased a young JM and planted it around April 25. Shortly after (in early May) we had an overnight frost (the temps dipped to about 30 degrees one night) The next day it was back up to 60 degrees. All the beautiful leaves withered up and fell off one by one but there is plenty of new buds growing. The problem is, as soon as the new leaves emerge and get fairly big, they also wilt and eventually fall off. With all the new buds, why are all the leaves dying?

Is this JM doomed? I have a one-year guarantee on the plant, so I could take it back, but I want to hold out hope that this will eventually thrive.

thanks for your input.

Kelly in WNY