This is unfortunately not unprecedented. When you apply for API access to facebook's graph API, you also need to document your app including videos.

The video isn't really that hard. You just make a screencast of yourself downloading email while saying "now I'm using the download email scope", and then sending email while saying "now I'm using the send email scope."

They don't care if the videos are terrible quality, it's only for them to understand what they're approving, and to have some documentation if a developer later changes an app to do something nefarious.