The Engineer's will talk. Subtitles or human, David narrating? What will their v

I have allways insisted that the Sacrificial Engineer was decomposing at the water fall, it seemed so obvious of deconstruction, not reconstruction, with top back part of head collapsing in on itself and entropy to body as it gazes at the effect of the ancient elixer on its hands and arms in fascination, wonderment. That scene has allways amazed me, as I saw a creature who seemed to be invincible willingly accepting it's fate, either for a greater purpose, like being abandoned by the big disc shaped spacecraft at the waterfall because of rescources running out (Dying race theory), or possibly him being an Engineer contaminated by his own mistake, and being effectively quarantined, dropped off by compassionate crewmembers on an uninhabited world to live out the effects of his mistake. He seems to be looking upon himself with no fear, just curiosity at his demise. I came to this conclusion based mostly on Vickers speach stating all kings have their reign, and then they die, it's ineviteble, that seemed to suggest power, and willingness on the part of the Enginer to accept his fate. I did not see the first human, as others have suggested or David, Holloway etc, based on his statuesque, godlike structure, hairless body and bearing of an engineer. In hindsight he will probably be some beings "Adam", if not ours. It is now known through the interview, and I am not here to say whether said interview with actor who plays Sacrificial Engineer is legitimate or not, if you do know of it's legitimacy or illegitimacy, enlighten me, he will have lines that he had to remember in an alien dialect close to the filming of that scene. Do you think that we will have subtitles as the Elder Engineers on the saucer bestow this honor on him and he accepts and does his ritual at the water fall, or we will just get a human voice narrating, or possibly David explaining the proccess later after being familiarized with their language? Weyland industries also has that nifty language translator that I would take on a voyage beyond our system. Can you imagine if the warning in Alien from the Derilect ship in Alien is tied to this. Nostromo navigator Lambert said that the warning sounded like a voice, or speech.