Does it go something like:

"Goin'Home; goin'home;
I'm jes' go-in' home.
Quiet like; some sweet night;
I'll be goin' home."

And does the melody sound like something you may have heard as a piece of Classical Music?

If so, then Mr. Dylan can hardly take credit for it, as it is an old Negro Spiritual which predates the American Civil War, 1861-5.
Alas, it is not to be found in the Mudcat DTDB. Perhaps I may remedy that absence, if any would like.

Some of my CW Reenacting Friends have worked as "Extras" on that film and are a little critical of some of the liberties taken by the Producers in the area of "authenticity", which is as you may know can be a sensitive issue among us Reenactors.

If they used a modern, Bob Dylan piece in the soundtrack in stead of a period Spiritual, I for one would be sorely disapointed.

When the film does come out, surely a lot of us will have to see it, if for no other reason than to look for our Celebrity (if but for a fraction of a second) "Pards"!