You can install youtube-dl and configure the bot to use it. Afterwards you are able to playback URLs from every source youtube-dl supports. However, there will be no support for youtube-dl related issues.
Download youtube-dl from the website (the version of your linux distribution is probably outdated)
edit the config.ini and change YoutubeDLPath = "" to YoutubeDLPath = "/your/path/to/youtube-dl"
On launch the bot will tell you if it found youtube-dl and if it’s compatible.
Some websites don't allow downloading, so make sure you don't use the bot for those sites.