Just click the "Lyrics video" button, it will then redirect you to a search page for the lyrics video. If you don't see the correct video, then the video probably doesn't exist. If it does but the script failed to find it, or if you encounter any other issues, feel free to open an issue here, or contact me on Discord: @NorbiPeti#1869 or Reddit: /u/NorbiPeti
I have plans on extending this to any other site Monstecat is on and adding plaintext lyrics support.