So yes I see the allowedBiomes however just having this isn't enough as the mobs are spawning in other dimensions like certain dimensions from Mining Dimensions mod, caving dimension to be specific, which is not supposed to spawn mobs. Most likely this is due to the fact that the biome it uses is the same category as the mobs allowed biomes.

Removing this biome category would affect the overworld, so if there is a way to add Blacklist, I can blacklist the exact biome, instead the category, or even better, a dimension blacklist would be amazing.