Cache is not at the Posted Coords, However it is within Walking Distance!
If you completed the Adventure Lab Castle Kilbride and the Prime Minister's path, then you would of been given the final coords to find this Bonus Cache.
But because the Prime Minister statues have been removed the Adventure lab has been disabled.
You are welcome to get this by traditional means, by using these final coords.
N 43° 24.234' W 80° 40.150'
You will be looking for a Bison Tube