Two solutions I use to identify deleted/private videos in YouTube lists:<p>1) googling the ID part of the video URL to get/guess the title at least<p>2) <a href="https://web.archive.org/" rel="nofollow">https://web.archive.org/</a> (surprisingly it even has wholly archived videos for some URLs - random example: <a href="https://web.archive.org/web/20150111045309/https://www.youtube.com/watch?v=Nn-BkBcbqhA" rel="nofollow">https://web.archive.org/web/20150111045309/https://www.youtu...</a>)