To borrow a concept from the Ghostbusters, you're crossing too many streams!
Taking a few steps back and framing your enquiry as a series of questions, we get this:
- Can a movie (be made to) emotionally affect the audience who watches it? Yes, definitely - we already have "feel good" movies, and there's a relatively recent example which escapes me of one feature being pulled from cinemas because it triggered violent reactions from at least part of its audience.
- Can a soundtrack (emotionally) affect an audience - I can hear all the sound guys shouting
"well, duh!" 
Yes, of course - we wouldn't have so many examples of good and bad soundtracks if sound didn't contribute
significantly to the feel of a movie (or stageplay, for that matter).
- Can you affect human behaviour with subliminal messaging? Yes. That's well-proven too. However, the vast majority of experiments rely on defining a very, very specific objective, e.g. ensuring that hungry cinema-goers buy a WillyWonka Chocolate Bar - and no other - when they pass the concession stands on the way out. It's a lot, lot harder to manipulate ill-defined abstract aspects of human behaviour with simple, single-strand approaches.
- Can soundwaves tuned to a single frequency do something other than be heard as a musical note? Oh, yes - and this is where the solfeggio frequency claims start to come apart: we have loads of examples of resonance doing stuff - but it's almost always
destructive. It causes bridges to fall down, glasses to shatter, rocks to split apart, water to boil ... You can take a pure sound wave, direct it into someone's body and blitz their kidney-stone into harmless fragments. So it's very possible to do
something, but these effects all require the frequency to be sustained, and to be properly tuned to the target, and - if you're going to demonstrate that a particular frequency has a positive effect - not be contaminated by other noise.
This last point means that you can't introduce a behaviour-modifying sound in a
subliminal fashion. If the frequency is part of the viewer's regular soundscape, adding micro-seconds of it to the movie soundtrack won't introduce anything new; and if it's not part of their usual auditory experience, then they'll
hear it and start trying to intellectualise it's relevance to the moving images and the rest of the soundtrack. That'll break the experiment.
All-in-all, you'd have to invest an enormous amount of time, money and energy into chasing a completely unfounded theory, when it'd be far simpler to use the sensorial experiences that are already in use and proven to work.
) but most traditional Irish slow airs, when played on a whistle or (uilleann) pipes include passages that pass through these frequencies when moving from one classical note to another. This is a characteristic of many traditional musical styles too.
).
