I agree. We know there are branching event-chains that happen according to player choice or interaction. If there are some, then this trailer would show what happens when things go wrong.I mainly think that's just a way of showing "What if things go wrong" - unless that is set in the plot that he dies at (an early?) point in time. Chances are if done more subtle, less with guns blazing, he would've made it. Assuming this is an actual mission aspect and not just a symbolic trailer showing something that is not exactly part of the game.
However, I am 99% sure this trailer was something that was specifically cooked up for this presentation, it is unlikely to actually show things as they happen ingame. In other words, what we see in the trailer may not even happen ingame. It COULD show cutscene footage, but I doubt it. Not even as one of the optional paths.
Kind of the same way how Marvel and other big film companies have started to blatantly lie in the movie trailers, showing scenes that don't even make it to the movie itself.
I just can't help but notice how the V in this trailer looks different from the earlier footage, and bears considerable likeness to Josh Keaton, the voice actor for male V. Prolly face-acted if not movement-acted the scenes. I am reminded of the behind-the-scenes footage of how the release cinematics in WoW: battle for Azeroth were created.