I don't believe we have a document that shows how to add the YouTube player via a rule in Launch yet. Can you post a screenshot of the error you got?
It looks like you're using one of our third-party extensions available within Launch. Since the extension is not built by Adobe, I have limited knowledge and experience with the extension.
After a quick search, I did find a YouTube video from the creator on the extension. Feel free to review the video and see if it provides any information that might help you solve this issue: