Not the answer you are looking for, but I have had to manually make the metadata for several documentaries or odd TV shows that I have. I essentialy make a tv or movie sheet in Thumbgen, and then enter all the data I can find from the Internet, cover, backdrop etc, and then copy stuff either from IMDB, or amazon, wikipedia etc. Fill in all the fields and then save it. Takes a long time but when that’s my only option, I go with it.