This happened on a railroad trestle in Indiana..the women were walking across when a train approached.  In the video, you can see there's no where to jump off the tracks, and if you can't outrun the train, there's one quick solution.  I imagine this would've been the same issue in Georgia with the filming on the Allman Brothers biopic; except members of the film crew didn't get out of the way in time..  The women escaped serious injury - but now they're wanted for trespassing.