Greenland controls half of one end of the northwest passage. The other end is controlled by the US via Alaska and the Bering strait. Doesn't seem like there's much additional benefit to justify burning a bunch of international goodwill on the matter.

The northwest passage can be done by going through the Canadian archipelago. Greenland doesn't really factor into the northwest passage.

You can do it all via Canadian waters and you can't do it at all without using Canadian waters so no need to even consider greenland as they don't have any waters that would speed up the transit.