This chart is specifically the death rate. The other charts you provided are “affected by” aggregate statistics or “undernourished” if I understand correctly.
It seems possible that NK is improving on people dying directly from it or deaths are being categorized differently (if everyone is malnourished, another more immediate cause of death may be recoreded).
So I’m not sure this is entirely wrong.
Not true, Norway is remarkably warm compared to similar latitudes (i.e. Canada) due to the Gulf Stream and the resulting coastal current. If that collapses the sea will freeze and Norway will no longer be the mild climate it is now.