I just went there today for dinner.
First, I went to the quick service counter. The guy asked if my order was for there or to go. I told him I was going to eat there.
He explained that the quick service window is only for ordering food to go (i.e., take out).
If you plan to eat at the restaurant, go over to the entrance, and someone will seat you and give you menus.
(The crispy chicken sandwich was good, the fries could use more salt or something. There were also a couple pairs of ducks waddling around.)
So...if half of your party is doing quick service, they can order their food from the quick service counter, but they can't eat it at the restaurant. I'm guessing they'll have to find picnic tables or something.
If they want to eat in the restaurant, they have to be seated with the rest of you from the start.