Unless Capcom is lying, they just confirmed that it was real time and this is using the ingame engine-
Capcom press email- “Following last week’s announcement that Capcom currently has two titles, Resident Evil: Revelations and Super Street Fighter IV 3D Edition (tentative title), in development for the Nintendo 3DS the first trailer for Resident Evil: Revelations has just been released and is now available for download from our press extranet. Featuring appearances from Chris Redfield and Jill Valentine the trailer is rendered in real time using the game engine.”
Spread that around and be proud. This should shut any skepticism up.
NEVER judge a game you have not played. -Granville