Trees, Shrubs and Conifers: is it dying? Chamaecyparis lawsoniana 'Imbricata Pendula', 1 by bonitin

bonitin wrote:
I bought this young tree (Chamaecyparis lawsoniana 'Imbricata Pendula') beginning of November and have planted it in my sunniest south-facing spot (although there has hardy been any sun at all in this dark period of the year) on top of a small hill in the best soil and with excellent drainage, the soil is moist but not soaked.
When I bought it it had already a little browning here and there, but I didn't give it much importance at the time. But now I'm afraid it is dying as all of its greenery has turned brown. When I checked the main stem, it still has green under the bark, but the branches look like they are drying up.
Is there still any chance this small tree would resprout from the main stem ?

here's a picture of it when I bought it;