We had a bike and hike trip there a few years ago. We had the group area and had to hike to the toilets and get water.
The group area had no shelters, but this was 6-7 years ago. Primary route was to be Empire Trail Rouses Point, motel, then head south on 2 to Burlington
I have an out from Plattsburgh to South Hero to 2 via ferry if the weather turns.