I winter my hinoki just setting on the ground in the north burbs of Chicago, a much more severe climate than yours. Winter is not the cause of your problem.
Most likely the problem is you kept too much of the old soil when you repotted. Now you have a pot where the media is not uniform. The new media is likely drying out and the old is staying too wet. This is my guess. I would check roots, maybe bare root and repot into fresh media in spring if you agree with my conjecture.