According to Dr. Anil Biltoo of the University of London (the fellow seen early in the film giving David his language lesson), THIS is exactly what David said to the Engineer at Weyland's request:
ida hmanâm aî kya namrrtuh zdêêtaha. gwhivah-pyorn-îttham sas daatrr kredah.
This man is here because he does not want to die. He believes you can give him more life.
The Engineers' language, as seen in the film, is Biltoo's own reconstruction of the Proto-Indo-European language. http://en.wikipedia.org/wiki/Proto-I...opean_language
So David DID deliver Weyland's message, with no ulterior motive. It was simply the wrong question to ask. "He chose...poorly."
Here's the article I got this from: http://thebioscopist.com/2012/06/20/...-the-engineer/