That model gen is noisy and you will need to run it most of every day but the park won't allow it. You just "can't get there from here"
You need more battery, and a higher amp charger to just get by. "Some solar" won't do you much good either since you would need lots to make any difference.
It is going to cost money to prepare properly for this trip. Who are these tent campers anyway? If it is a group that you will be doing this with every year perhaps you can pass the hat so they can all chip in and the "group" can own the "extra" things needed. But then somebody has to maintain the extra batteries for the rest of the year on a trickle charger.
Whatever it is all about, more preparation is needed to make this an enjoyable event, which it can be of course. RVing is good for you! :)