I played through and got one ending. I don't want to replay if I risk getting the same ending again or retread a bunch of the same content, is there a guide somewhere?

A lot of ways to get soft lock in the game. If you don't use the bike at the start, you can't interact with it again. It happened again later, near the bunker when I needed to refuel it and had no option to refuel it despite having fuel. Also in the ending dialogue, a lot of option end with "give me back my son" and no option to continue the dialogue......