This happens more often then you think in the snowbird circle. The times that I'm aware of no-one had a plan in place. Most often fellow RV'ers will take care of things, no questions ask, or payment expected.
There was one time where the DW after her husband suffered a massive stroke decided to continue the adventure. She did EVERYTHING and did a very fine job of it while her DH stayed inside. They had a nice DP, an American Eagle if I remember correctly. She never drove the rig prior to his stroke. They were seeing the USA as they planned during their working years.
My neighbor down south passed away, once again there was no plan in place. His wife decided to go FT. A fellow female snowbird hoped in the rig and the two of them drove back to Canada for the summer. In the fall she drove the rig south alone.
You do what you have to do.