first rightsx
Why does my cover song status say "Custom Required"?
International Copyright
The most likely scenario is that the song is not published in the US and/or does not have US publishing representation. A compulsory license cannot be issued in this case and the rights holder must be contacted for a direct licensing agreement.

Changed Lyrics / Melody
Any changes to the lyrics or significant changes to the melody are not permissible under a compulsory license as it constitutes a derivative work. Derivative works must be cleared directly with the rights holder. A "derivative work" is any song that takes a preexisting work and uses that material to create a new composition. It differs from a cover song, which is a more straightforward interpretation of an existing composition without significant alterations to the melody or lyrics. Examples of derivative works include: - translations - sampling or replaying (re-recording a segment of the original song) - parodies - medleys - songs arrangements that change lyrics, abridge the music, or make other significant alterations to the original composition. -writing completely new lyrics to an existing composition Clearing derivative works is very difficult. The copyright owner can set any price, take all the time they want, and reject the permission altogether. For this reason, it’s important to temper expectations when making a derivative request.