Hi Kassy, I don't know the rules, but I do know that it requires special permits to enter North East Greenland north of Scoresby Sund by sea, and there have often been doubts about the legality between the lines in articles about cruise ships in the area.
Not only that, rescue operations in the area are extremely expensive and difficult to carry out due to weather, distances and many other challenges.
But the Danish police, I know, are investigating the episode?