Couldn't find any official ruling on that.
Determination Dark Virtue Reaction: Before you announce an action, target one of your Samurai: The action can not have its effects negated or have its targeting changed. After the action destroys any Personality, remove him from the game.
Hida Sozen exp Other players' actions can not destroy Sozen.
Ok, so can I destroy Sozen exp with, say, Hired Killer, assuming that I also played Determination? I'd say yes (Determination explicitly says that the effect of the action - destruction in this case - cannot be negated), but..you never know
Thanks