Seems to me that if GNR were having a song on the DVC Soundtrack, then Axl would have mentioned it the other week to the RS journalist...
Also, the DVC trailer is now in cinemas, and I don't hear anything on it that sounds like GNR. Surely, if you had GNR on your soundtrack you'd advertise it...?
Trailers often employ music that isn't on the actual soundtrack itself-particularly if its still the 'teaser' trailer. For example, the Superman Returns trailer is using the old Williams' score but the picture itself has a whole different composer.