Hunter's Potion on Ivern
I imagine that this is simply an odd coding mechanic that was either not considered or overlooked.
When Ivern "frees" a camp while his Hunter's Potion is at 5 charges, it does not automatically activate a charge. Instead the charge is wasted.
When you have less than 5 charges, you do gain a charge from "freeing" a camp however.
My theory is that the code does not consider "freeing" a camp to be killing a camp for this mechanic. Ultimately, I could work with it, but I think it should just activate a charge like it does for everyone else.