Just a couple of points.
The park is considered closed at the published time. It's just after the fireworks. It's not cleared of guests but it is closed to new guests. They will not allow anyone in after that time, just out. I wouldn't count on getting in thru the IG in order to walk to the front if it's after the official close time.
Also, if they haven't used an admission to Epcot that day or used a park hopper, they will have to use one to walk thru the park.
Having said all that, we do try to "make the magic" when practical and sometimes we'll buy a sob story. So we might let them walk thru to the front without using up a ticket.