Has anyone ever managed to get that quest finished? I replayed this game so many times, always scoured every inch of Alvar but the quest giver ALWAYS tells me, I didn't kill all ogres. Is there some secret place I forgot to check? This is driving me crazy, I just want to finish this quest for once in my life.

The similar quest with the wolves works without problems but this one just doesn't.

I always find and kill all of them.
- check the hills in the NW corner
- you need to clear the ogre stronghold
- use Wizard Eye!

you can make sure its not bugged by popping armagedon a couple of times after clearing the stronghold

The next question is have you cleared the lower levels of the fort?

https://www.zimlab.com/wizardry/recovered/flamestryke/mm8/flamestrykes_mm8.html

I finally got it. It's still bugged however. The way to do it was to repeatedly enter and leave the dungeon. After the sixth time the message finally popped up

Are you playing the last official version of 3DO/NWC, from 2000/2001 ? If so you need to get the Grayface patch