VoxWav works completely different, because it send a recorded audio file to VoxCommando which does then the speech recognition.
One thing what you can do, is to edit the "custom slot types" in your VC Alexa skill in your Amazon development portal (see picture below), but I'm not sure if this will help a lot.
You can put (for testing) the complete movie title in, but type 4th how it will spoken "fourth" or type only fourth July - maybe this will work.