It doesn't really make sense to. The idea of a sending a token force is to act as trip-wire. A trip-wire force is there so if they're attacked, it means war. In that case, those soldiers would be reinforced. They're the tip of the spear.
If Canada sent a trip-wire force in Greenland, those soldiers would not be be expecting reinforcements if attacked by the US. Because Canada is on the border with the US there would be fighting much closer to the aggressor than where the trip-wire forces are. So it would be sending soldiers to Greenland and telling them if attacked by the US they will die with no hope of reinforcement.
You put trip-wires on your outer defenses between you and your enemy. You don't put them far away from the front-lines of a potential conflict. Doing that is just telling soldiers to either die or surrender if attacked.
Remember they're soldiers not some pawns on a chessboard that you sacrifice for a phony political statement. Really what would be the plan to reinforce Canadian soldiers sent to Greenland if they were attacked by US forces?