Best of luck. Get a middle man if you don’t want to deal with it but if not, before speaking know exactly what you are looking for: Where will this screen with this music in place and on what very specific platforms? How exactly do you want to use? do you need stems? Instrumental? Clean? Tell them now. Who exactly owns the master and who owns the publishing of the music you want to use? How prominent are the sponsors in the film? Where will this stream again? Specifically.

I’m surprised you haven’t heard back from the labels. Let the new year settle a little and get this in people’s brains. Call any number you can find on a label website and get transferred for a bunch before you find the people that handle sync. Reach out to publishers too, you’re gonna have to speak to them anyway. They’d be able to get the label’s attention for you, just know which label has the recording you’re after beforehand