You don't mention what happens on Tuesday when they become overdue. If they assume they will be reported missing on Wednesday, then they should stay with the vehicle and tightly ration their food and supplies.

You also don't mention how well traveled the road is. Knowing this might sway someone to stay.

Based on the equipment they have, I think I could stay there almost indefinitely if there are fish or game around. But I'm not a Mr. and Mrs. Weekend Car Camper.

Back to the walk out... The low road is safer and warmer - that's the road they should take.

If they decide that staying with the car is hopeless, then the first thing is they need to stick together to walk out. They also need to leave a note about where they went. Third, they need to stick to the logging roads and not take any shortcuts. They should also figure on about 6 to 8 miles a day and ration their available food for a 10 day walk.

The items they should take... going down your list... they will need to build backpacks from sleeping bags. I say ditch the heavy tent but take the rain fly and cut the bottom of the tent out for a ground cloth/tarp. I would keep the hatchet and both knives. Ditch the coolers and dishes but take the water carrier - with only about 1 gallon or less, and bring as many of the small plastic water bottles they can full of water, and bring the percolator. Rip the one page that matters out of the map book and keep the rest of the book for tinder. Take extra clothes/layers to stay warm but ditch the fleece blanket and the foam pads. Of course, they need to take the matches, lighter, and flashlight. Overall, my idea is that they should be under 20 lbs of gear or less per person since they do not have boots.

They can't carry a 5 gallon water jug full of water. They should carry all of the small water bottles full of water - as many of them as they can carry up to about a gallon each, plus about one gallon in the big container.

They should also take some items from the car... a mirror, along with quite a bit of wire which could have multiple uses. A hub cap might become a bowl (I got that one from dual survival). What I would do is walk around the car very very slowly and meticulously go over it inch by inch and ask: What is this item good for, what are it's qualities, if I break it apart what are it's individual qualities... that exercise might yield surprises, like using the seatbelts for backpack straps. They might also find some good tinder items in the glove box. The tire iron might be handy for digging. One person could carry the hatchet and one carry the tire iron. They should also take some of the gasoline from the car and keep it in a water bottle. If they slow down and take their time going inch by inch over the car, it might yield a lot of goodies.

Another item from the car... Vinyl seatcovers could be cut out or vinyl backed carpet could be cut out to wrap the sleeping bag/backpacks to keep them dry.

They will need to create a first aid kit to take with them with one of the primary goals of preventing and treating blisters. Fresh socks and baby powder would be helpful. So would duct tape. Electrical tape from any wiring in the car could also become a blister bandage.

Once they've gathered supplies, they would split it all up into halves and put each half in a sleeping bag and then roll it up. Then roll all of that up in vinyl carpet for dryness, then tie on seatbelts... that makes up the two backpacks. Might need to make one of them lighter than the other for the lady.

A 10 day hike in those conditions... they would need to filter found water through a t-shirt and boil it. They would need to ration their 3 days of food over 10 days. They would need to leave signs of their progress as they move. They would need to stick to the logging roads. If they come across fish or game, they should stop and rest for at least a day and take in protein, then proceed. Otherwise, they should press on at least 6 miles per day.

That's about all I can think of for now. I think my main point to add to this discussion is that I think it would take them 10 days to walk out and they would need to realize this early on or they would become demoralized. Second to that would be my point that they should not carry more than 20 lbs. per person on their backs.