We were working with support on the issue of a YouTube Link not playing, as it turns out since the link was private GTW could not play the video. In our discussions the Support Technician (his name can be provide for further information) we thought of a possible solution that may make this possible. If GTW would include an entry in the Engage Attendees - Videos, under Link YouTube Video to allow the input of the YouTube Account that has either been granted persmission to play the Private Video (YouTube Invite) or to the account that hosts the private video on YouTube, which ever would complete the connection. This might allow for the playing of private videos from YouTube through GTW.
It was just an idea that might be worth investigating, to enhance the availble features of GTW