Yes, released officially by Queen's record company in Japan, Toshiba-EMI.
Here's the history:
Greatest Karaoke Flix, 2-laserdisc set released in 1996 (Toshiba-EMI TOLW-3249) (also VHS)
Greatest Karaoke Hits 2 CD set (soundtrack to the laserdisc), released 1998 (Toshiba-EMI TOCP-65061-62)
Greatest Karaoke Hits 2 CD set (remastered + 1 bonus track) released in 2004 (Toshiba-EMI TOCP-67422)
Greatest Karaoke Hits DVD (+4 bonus tracks) released in 2004 (Toshiba-EMI TOBW-3174)
There are a total of 35 karaoke mixes officially released (the DVD has them all)
There is also a digipack DVD/2 CD box set of the remastered 2004 stuff in a Korean version (Parlophone-EMI EKPDV-0014) which may or may not be truly official, but the contents still are ;)