Nameless Seer never spawned

I had a map which has the mod "Final Pack spawns the Nameless Seer on death" as you can see in the screenshots there are 0 monsters remaining and the nameless seer never spawned. I did all league mechanics in the area and ran through the entire map 3 times to ensure I hadn't missed anything. I even tried to log out and back in, still no luck. There was a delirium mirror, jun, a breach as well as a blight encounter if that helps in any way.