Thanks to everyone. I am still a bit confused, but I will investigate further.
According to the internet, the vehicle itself weighs about 6,000 pounds. Add five healthy adults and their luggage, and it seems like we'd be reasonably close to the 7900 GVWR on the card. So that would mean I could tow....just about nothing. I will continue to investigate.
My understanding of it, is that with a full load of passengers, you will be very near payload capacity. If, for example, you have a 3000# trailer, your tongue weight should be 10-15% of that, so between 300-450#. You need to be mindful that your payload (passengers/gear INSIDE the expedition) + tongue weight + unloaded vehicle weight (UVW), also known as “curb weight”, doesn’t put you over the GVWR, 7900#, in your case. Without HD tow, I believe yours will be rated to tow around 6000#, check the Ford tow guide for your year online for your specific model/build options. Weight of passengers and gear + tongue weight will likely be what decides how heavy of a trailer you can safely/legally tow.