Hello ,
Thank you for reporting this and your patience as we have addressed this problem in the official release 2022.1 that came out today. Please update your Twinmotion from the Epic Games launcher and try to export your media's with the video textures.
If you encounter any further issues or bugs please use this link to report them:
https://twinmotionhelp.epicgames.com/s/case-community-page
Kind regards,
Vincent B.