I’ve encountered the following problem when using ‘Get Videos’ Helix endpoint. The value for ‘published_at’ field is ‘null’. ‘created_at’ field has a proper, non-null value. If I open such video in Twitch, there is also no publication date mentioned.
Example of video: https://www.twitch.tv/videos/367596992
This looks like a Twitch bug, and I hope this ticket is noticed by someone from development team.