Seems like Vivec wrote this . Do you mean, you want to make a video of a cover version of an original ESO track with your own lyrics and vocal performance to participate in some contest, and you ask if you may do it without paying a royalty fee for implementing an intellectual property owned by the property holder into your own one, and without violating their rights? Or is it a question about using some in-game music in, say, your youtube video?

By the way, this is what Vivec says about voices, royalty and other such things :
"All language is based on meat. Do not let the sophists fool you";
"The truest body of work is made up of silence: as in the silence that results from no reference";
"When you come out of the vocal, you can never be certain";
- The Thirty-Six Lessons of Vivec, Sermon Twenty-Seven, Scripture of the Word.
"The secret syllable of royalty is this: (You must learn this elsewhere.)";
- The Thirty-Six Lessons of Vivec, Sermon Thirteen.
"'CHIM,' which is the secret syllable of royalty".
The Thirty-Six Lessons of Vivec, Sermon Twelve.