Galapagos trips are usually active travel experiences where you explore the Islands hiking and you explore the marine life by snorkelling. As you said the landings are by zodiac and the terrain is dificult. It is not recommended she take a cruise to the Islands.There is though accessible options. There are several visitor sites that are not dificult and that the landing zone is quite easy to reach, there is also visitor sites on some of the main Islands that do not require a zodiac landing and can be reached by staying at a local hotel. If your heart is set on the Galapagos you can book an Island hotel with land tour combinations and select visitor sites with your tour operator that do not require zodiac transfers and long strenous hiking. My recommendation is that you stay on Santa Cruz Island a few days and visit:Charles Darwin stationHighlandsTortuga BayGlass bottom boat bay tourDay trip to North Seymour IslandDay trip to Santa Fe IslandDay trip to Plazas IslandYou can combine your trip to the Galapagos Islands with a stay in Ecuador, there are many attractions with easy access as:Otavalo MarketQuito´s colonial downtownPapallacta Hot SpringsArasha Rainforest SpaAmongst others.A good tour operator to contact is Galapagos Cruise at reservations@galapagoscruise.com.ec