Honestly, I would not spend that much time in the tent post race, either day. On Saturday, I would head in, have a small snack then get back to the CR and clean up. I would then hit my big meal of the day in preparation for Goofy. I would spend time in a park or walking a resort to stay loose. If you are budget challenged and do not want to spend $$ on a pass, walk from the CR to the MK monorail station, then pass that station and walk all the way to the creek; like you would be heading to the GF. Its a nice 5k walk on all the memorial pavers.
For meals, look at the GF Cafe Saturday afternoon/evening. The chef (as all sit down places will) has a pasta special, but will also have enough stuff to prepare whatever you wish.
I think your strategy is sound for the race... Half as the goal and marathon as the filler for Goofy. Note that makes moving Saturday more important to keep legs loose. Hydrate Saturday. You will feel stiffer than normal on Sunday AM, but the hill at mile 1 will help loosen the legs. Also, you will feel the half a little early on Sunday, but it will still be very manageable.
If this is your first mary... expect your kidneys to not function well for a couple hours post run. You should not get too far from the area until they recover. You will know when that happens

Use Tylenol and BioFreeze post race to aid with the stiffness. I would walk as much as you feel comfortable. Wear you medal!
Finally, I am a big believer in compression tights/hose post race. With you getting on a flight, I would really suggest them. While the likelihood of issues are small, they will support the tired muscle and help lessen the micor bleeds, eliminating some of the soreness.