The most nearly authoritative people are academics, and we see that their writings usually end with a (sometimes large) bibliography. In other words they don't rely on anything like one source.
Further , there is the informal law,"For every PhD, there's an equal and opposite PhD." Even "authorities can disagree, and scientists argue.
Other people being taken in actually is a problem for all of us because anyone taken in by incorrect information can thereby do things which are dangerous, annoying, problem-creating.
As for Ms.Davison, your point wasn't clear Folkiedave, but I saw the movie of Davison and the King's horse, and she is clearly show avoiding horses once she's on the track because she was clearly seeking out a particular horse.
One line of persistant error about which i have a collection is of Popular Fallacies. E.g.Historians have known for a rather long time that King John didn't sign Magna Carta, but the error has persisted for nearly 800 years and counting. That's just an example, and for the record, the reason is that John was illiterate. What he did was seal it