What about the nearest accommodations such as overnight staying with children?

I'm not sure about that camp ground at the beginning. It looks like people might live there in campers and it appears to be very crowded and close

Yes very close

There are many hotels, campgrounds. Very near by. Even splash lagoon and their hotels are only a 15 min drive. And waldameer park and water world is at the beginning of presque isle

There is a campground at the beginning of the park also a hotel one block before the park.