Just finished the doc. Definitely worth viewing. It's kind of a bunch of mini-docs on each episode. However, conspicuously absent is any mention of the Luke reveal in the finale.
They went to insane lengths to keep it secret. In fact, according to people who work on the dubs for foreign markets they weren't even allowed to work on the back half of the last episode until the last minute. No way they were letting the documentary crew on set for it, I'd assume.