What is a narrative? A story that explains why things are the way they are, or why the current situation is unacceptable and must be changed. The farther from the truth, the more outrageous, the better. Only fools believe the narrative.
Example: Black folks are victims of white oppression, they’re not responsible for their station in life and only the Democrat Party can save them. Standards must be lowered and concessions must be made. The Founding Fathers were aristocratic slave owners who crafted the Constitution to favor white people. The system must be changed.
That last statement, of course, was the goal all along, but it had to be justified (which is why you invent a narrative). Another example: Global warming. Goal: Massive government involvement in your life.
The narrative for WHB contains several elements, here’s one of them: They were simply turned loose or escaped from nearby ranches, no special significance.