ToME: the Tales of Maj'Eyal

My Yeek anorithil has been proving quite entertaining until the master didn't spawn where he should have. Anything I did wrong or should he have spawned? No game crashing on zoning or anything like that. Any help or do I start again?

Do you have any means of detecting creatures in large radius? He might be in hiding.

Also if you're familiar with room structure and stuff Dreadfell you can try to figure out where to dig for him.