A barium meal is for finding leakers within an organization. IF you send material to a journalist, unsolicited, and they report on it, what exactly have you established?
Like, do you think they did the same thing with multiple journalists in an attempt to see who would publish and who would keep their mouths shut?
Bear in mind, when you join a Signal group you don't see the conversation history from before you arrived, only the live updates that take place during the time you're a member. Also, anyone in the group can view the list of group members and receives notifications about people being added to/removed from/leaving the group.
I can't buy this, because everyone in the group can see who added other members (at least until disappearing messages time out that information). If it was just someone leaking they could do that by taking screenshots of the government group and then sending them to Jeffrey Goldberg in a separate chat.
Like, do you think they did the same thing with multiple journalists in an attempt to see who would publish and who would keep their mouths shut?
Bear in mind, when you join a Signal group you don't see the conversation history from before you arrived, only the live updates that take place during the time you're a member. Also, anyone in the group can view the list of group members and receives notifications about people being added to/removed from/leaving the group.