Mith'rethis the Enchanter spawn location/respawn time(Icecrown) ?

Hello, I have been running around the Hinterlands WoWHead location for Mith'rethis the Enchanter rare elite encouter and have not seen him, I have been using a macro : /target Mith'rethis the Enchanter to try and get him if I am in range but I have yet to see him. I have 2 questions.


1. Is he even in the game
2. If so, what is his respawn time ?


Thanks !

Somewhere in comments was written about 12h respawn. But depends if it works correctly here.