It doesn't matter where you kill the Minotaurs however you can only hear the messages if your in the back near the temple/courtyard and the road that leads to it where there are the two booby traps.
If you've been at it for two hours your not killing them fast enough.
I've cleared out the back many times where I had to go back to the entrance because that's where they all spawned.
Meraktus Protection Talisman>Meraktus Killer.
Tormented Protections comes in handy too.
It has been a while since I last did the Meraktus spawn but my recallection is of poor loot, at least not worth the time and effort it takes to get it done.
Did they change it to make it more worth the effort ?
Tormented Minotaur Statuette is a beauty!