I have a theory on the trailers. It might go something like this.
At the beginning of halo 5, it might ask you who you're going to be playing as first. Agent Locke or John 117. I think the campaign might work in a similar fashion to halo 2, where the gameplay would be passed back and forth from Chief to Arbiter, but in this case, Locke to Locke or vise versa. I think at the end of the game (presumably where these two trailers are located) the first person you pick to play as will be the one interacting with the other. So if you picked Locke at the beginning, he will be the one to either shoot chief or let him live and such, vise versa with john.
As for the statues looking different for each person, its symbolism. In John's mind, he's worn out, has no directive, and can't decide what to do with himself after the "death" of Cortana. This is why the statue looks broken and smashed up. In Locke's mind, his views on chief are "perfect" and "savior". That Is why the statue is pristine and new.
In the end, we will have to wait and see at 10/21/15 for another trailer but also poses one question.
Which side are you on in Hunt the Truth?
Poll