I don’t think that Bellamy was right to choose to help those farm station survivors over the hydro generator. They could have saved them later after the generator was safe. They will now just die horrible deaths later on anyways, dying outside of captivity is no better then inside. Also, i think they could have come back with fifty soldiers with guns and taken care of that quite easily.
I just thought about Murphy hanging out with that girl in that cave. Maybe they will find some safe ground water somehow or just some caves they can live in. Maybe Murphy being in that cave has some greater purpose.