Bug: Wisps don't always go to the bottom of the Timeline

I’m currently in the Torture Chamber inhabited by the Wisp race, but sometimes when dealing damage to them, they don’t go to the bottom of the Timeline. Coincidentally, that’s also the times when my Mutated Pulse Bat’s trait doesn’t trigger if it’s an attack. Dealing damage to them via other means also sometimes makes the Wisp go to the bottom, but not on other times.

To be precise, my other forms of damage are Drained trait (where you deal damage if stats are being lowered) and the Mutated Pulse Bat’s traits. Using the Resonance spell (the one where you deal a massive amount to Silenced enemies) triggers some Wisps, but not all of them.

I assume this is a bug since the description pretty much states ANY damage.

I wonder if there is a bigger bug causing this, like the game not always seeing it as an attack or something?

Warm regards,
KaaaaasKop.