What "power" are you referring to? The power to get their products, which were misappropriated (maybe not stolen, but acquired under circumstances which should not have occurred) by others?
So out of curiosity, what would you propose that would be acceptable to both sides? On one side we have WoTC, who does not want people getting merchandise before it is available and wants to ensure that others in the future don't do what this YouTuber did. On the other side, we have a guy who may have accidentally gotten merchandise he shouldn't have, but would like to not be threatened and intimidated by a large and financially capable corporation.
What would it look like for you? What would the process be? What would you do if you were in charge at WoTC? And i'm going to pre-emptively state that saying, "I don't know," isn't a good answer. Because "I don't know" leads to this type of incident. I'm willing to bet that the guy who was in charge of getting this situation handled probably had no idea who Pinkerton was or the reputation they had. So how woud you handle it?