Is this person a member here? How did you contact them?
As a karaoke fan and at times when a song is not available commercially I would create the music with vocal removal softwares which don't do a good job at it. I have found uploads in YouTube and the one that impresses me most is the uploads of SmanusakSomboonsub. Examples:
Strangers in the Night (Frank Sinatra), And I Love You So
(Perry Como). I contacted Smanusak S. but I have not received a reply. He probably didn't want to reveal the secret sauce. I just wanted to know what software was used in making the karaoke music. Would anyone know?