GEORGIAPEACH, I think you are forcing your thinking too narrowly into what you want the answer to be. Look at the accumulated evidence and see what conclusions are likely. I think you will decide that pit stop #3 is in PUNTA ARENAS, probably starting the evening of Nov. 25. The teams then go to USHUAIA and not King George Island or Antarctica. I expect them to leave USHUAIA on the 936pm flight out on Nov. 28.
What are the likely transportation options? I have been scouring the Internet and I have found some more that are interesting. There is a second bus company in Puntas Areans which has connecting service to USHUAIA on the 4 days that were not serviced by Pacheco Bus Company. This service leaves at 830am instead of 730am and probably takes at least the 12 hours of the direct bus. Also, in addition to the LAN flights on Saturday, Monday and Wednesday from PUNTA ARENAS to USHUAIA, I have discovered that DAP "In summer, it flies Twin Otters to Ushuaia Monday, Wednesday, and Friday only (US$100). It also has extensive charter services. " That could be the answer on how teams get there relatively fast since as has been clarified for me Nov. 26 was a Sunday when no regular flights are scheduled and the teams must get to USHUAIA to be sighted that afternoon.
What would one see and do in and around PUNTAS ARENAS? The most interesting thing is too far away, the Parque Nacional Torres del Paine 250 miles north. Although Punta Arenas is a mid-sized city at 120,000 inhabitants, it does not have a wealth of top-notch tourist attractions nearby. The best to me is visiting the penguin colony at Magdalena Island 25 km away in the Strait of Magellan. I'll bet that van Munster/Doganieri found something to do in Punta Arenas, maybe an eating challenge.