Declined "Documentary" Genre contribution

https://contribute.imdb.com/contribution/261004-195013-481000/

I have a hard time understanding why this contribution was rejected twice as "factually incorrect". Watching this film, it is very clearly a documentary, narrated by Hugo Weaving. All cast credits are either "Self - Narrator" or just "Self", indicating that there are no fictional roles.

This review also names it a documentary: http://www.dvdinfatuation.com/2015/09/1852-wild-australia-edge-1996.html 

Finally, the movie is actually viewable on Vimeo, albeit with Audio commentary over the original narration: https://vimeo.com/585990515 

Is there any specific additional evidence you would need in order to classify this film as a documentary?