June asked Ryan if he wanted to learn to swim. He kinda brushed it off. It is very hard to learn swimming in the ocean, but it also shows us that he had time to learn in the past (I assume he really is a bit older than others in the group?) and decided not to in the end.
I think it was his choice to stay with them, you know... Like you can put these thoughts aside (about them being, well, not good sometimes) and choose to keep things the same even though you know them.
Anyway, that's my liiittle theory after playing the game eheh. I loooved your big commentary above!! <3