If you use duckduckgo to search for youtube videos that's the easiest way over that hurdle because DDG will show the length of the video as an overlay for the thumbnail. Just search for "17 minute timer" or whatever is the closest but less than the length you need. Make sure to sort by short/medium/long as well to limit it to the proper window.

Made it to "the length of your password must be included in your password" and decided to throw in the towel.