I was switching to my turret in the car and then just fell through the floor and ended up in Esparanza, exactly where you first take control of the game. Any possibility of this being useful to possibly reproduce it?

That is a pretty common thing actually 😊 When you clip through the ground, the game will spawn you there for some odd reason.

It may be useful for the full ending category, if you ever have to go to Esperanza and can't fast travel there. I have seen a lot of instances of this bug, but I don't know how to easily reproduce it. I'm sure there is a way though.