Spies on the ground? In Greenland? The largest town has less than 20K people in it! Who do we have on the ground there, the town gossip? A member of the PTA? Bartender at the pub?
Got to keep those spy satellites tasked on them or we might miss major events like Poul repainting his house a different color.
(Greenland doesn’t club seals - I looked it up, but that’s comedy)
If you think a bit longer term, and you're able to put say 100 people there, there might be able to subtly influence the public opinion rather easily. And this public might in turn later vote to join US and said US could come to the rescue.
I believe that's pretty much the plan - try to win the population, which is very small, by any means necessary - bribe (they already tried apparently), sow discord, find a common issue you agree on etc.
Many (most?) people spend much of their leisure time on social media, why should Greenlanders be any different?