Solution
Here are the ways to delete a video from the library -- How to delete a GoVideo from your library.
Once a video has been deleted, it is gone forever and anyone who tries to access it (perhaps with a link that was sent to them previously) will run into an error page indicating that the video does not exist anymore. If needed, to recover this video, please see the following article - How to recover a deleted video.
If the video is not able to be recovered, or if this is not working, please contact us at support@vidyard.com and the team will be able to determine if recovering the video is possible.