Is there a parking lot for additional vehicles? We reserved a 4 car lot and the entire group needs to come down with 6 cars. Just need to know if there is any parking outside of each camp lot.

There is a TINY area right outside the check-in shack, where a couple of cars can park, but it's not a guarantee that you can get a spot there... There is also a dirt lot down by the Christian camp that you might be able to use in a pinch, but that is a bit of a trek.

There is some credit honestly is first come first plan on leaving earlier than expected if it's going to be on the weekendplan on leaving earlier than expected if it's going to be on the weekend or if you know for a fact there is a big reservation in that area.

No there is not. Parking is limited to the campsite. For a single sight you can have 2 cars, for a double site you can have 4 cars. I would look for a double site to accommodate that many vehicles.