Not sure if working as intended, but the Ancient Spirit’s “Essential Dignity” trait is not proccing off of the Ebony Ent’s Mend. Not sure if this is just not meant to qualify as healing, but thought I’d throw it in here.
On-heal effects only occur if the creature was damaged (missing health) when it was healed. If the Ebony Ent was at full health, it wouldn’t activate. Maybe that’s the problem?
You are correct, I am mistaken and ashamed!