What team setup were you using? Do you have a screenshot (or video capture if possible) that we can analyze?
We should at least rule out the first two “usual suspects” that are Stun and Curse (both of which allow bypassing enemy Traits), Curse being the easier one to miss during a fast-paced battle.
This would not be the first time Despond’s final trait has been bugged.
Thank you very much for posting this issue. This interaction defiantly shouldn’t be happening, I’ve let the Development team know about this so they can start working on getting that fixed!