We're using InControl in the Rebirth of the Night modpack (we make HEAVY use of this mod, works for most of our needs ^^ )

Better With Addons adds an entity called Spirit. These spirits are non living entities (basically an XP orb but different color and uses), and by default, spawn when a very specific mob is killed. They must be collected by standing near them with an empty bottle. The spirits are used in a crafting table of sorts (the ancestral infuser), where spirits must be provided as part of the crafting recipe.

Well, we on the Rebirth dev team don't like how spirits only come from one very specific type of mob killed under very specific conditions, and would like to have the spirits instead spawn anywhere in the overworld at night time, so I assumed I could use InControl to do this.

When I added spirits to InControl, InControl threw an error when attempting to spawn the spirits.

Here are the InControl JSON configs I used:
Spawn.json:
https://gist.github.com/Kompreya/7ead9d7a0edf3a3cd8fe76617bede4d7

potentialspawn.json:
https://gist.github.com/Kompreya/041f6113a155b6d9856e5663db403a3f

And this is the error it threw:
https://gist.github.com/Kompreya/456cc028b9972765c3bef23ab8997ccf

I assume the NBT tag is required, because that determines how many spirits are in the bottle when they are collected. I've also tried it without the NBT tag.

I already talked to the BWA dev. They are not able to change the Spirit to a living entity.

My only guess is InControl can't spawn non living entities.