This is a small suggestion but could be useful in some way.
But I’ve noticed that a lot of high tier thralls can’t use the truncheon.
I have berserkers, dalinsia and a few other named that can’t seem to use it properly. They use regular weapons most of the time but they just keep standing passive with the truncheons. Which is quite annoying.
If there’s something I would like to see updated (fixed) it’s this little thing.
I think what you got there is broken AI. The thralls, including berserkers and the like will use a truncheon under the right circumstances. However, it’s really easy to break the AI by removing their primary weapon when it is equipped and replacing it with a truncheon. I agree that this particular broken AI is quite frustrating and should be addressed. In the meantime I would recommend running your thrall with a single handed weapon when preparing to look for thralls. It seems to break the AI less, when you switch to a truncheon.
@Zeropoint is right, this is actually a known bug. Assuming the the devs rework the thrall AI like they have said they want to it should be fixed with that if not patched sooner.
Try to not equip more than 1 weapon to them as they get confused when switching or being forcibly switched especially with a two handed weapon to a one handed weapon.