It's been suggested that what happened was a trailer-maker broke non-disclosure, got fired, got replaced, and thus the low quality: because it's stiched together between two different designers.
For those wondering how the trailer is "low-quality," I find it a bit dull myself but wouldn't call it low quality. I have however seen discussions by people who work with editing who will point out stuff I haven't even noticed and call it shoddy work. (again, sorry for not linking directly to this. Some of these discussions take place on sites I'm not allowed to link to here)
To my knowledge, Bethesda has never chosen canon when it comes to killable NPCs. AKA, we will likely never see a canon ending for New Vegas because anyone can die and 2 out of 3 factions MUST die off to a degree for the game to end. Lucien Lachance successfully recruiting you in Oblivion is never confirmed, as far as I know.