Moving files to and from Dropbox does seem to cause problems and there are already some workflows to do this. You could use your workflow to move your files into dropbox anywhere, then use editorial set up a folder structure in dropbox and to move your files into this structure.
Otherwise, you can find a parent directory in python like this:
p, n_e = os.path.split(full_path)
x,d = os.path.split(p) # d is the parent directory
And there is a function os.walk that might help you replicate the file structure; I've not done this.