The plane crash settlement and the forming of the board/purchasing the hospital are separate things. They all came into a bunch of money when they got the settlement, then it came out that the hospital was at risk of going under (or being sold to a shitty company), so they decided to buy the hospital. Callie acted on Mark (Sofia's) behalf for the purposes of the lawsuit, but she was acting as herself and on her own behalf when they formed the board and bought the hospital. Remember, they got Richard involved in the formation of the board when they needed someone with management experience to show that they actually had some idea of how to run a hospital. Anyone presumably could have come on board by buying into the group at that point, if they were open to it.