The story is a sad one, and from the comment "over corrected" it appears someone witnessed the accident who was close enough to ascertain what the problem was that led to the accident.
Was riding a few weeks ago near Hot Springs, NC -another fun twisty road - 209 (?) - & my riding buddy failed to negotiate a turn on his softail & almost went off the other side of the road AFTER he went over the double yellow line in a sharp turn. He told me later he had a brain fart & just over reacted. If he had gone 2 feet further, he would have over reacted into a rock wall. Big accident reason - over correction in a curve.
Last time through the Dragon I stopped once - for a travel trailer pulling a trailer. It was well past the line in the corner & no way could the driver negotiate that turn pulling that much behind him. Best to stop & wait but some bikers just try to keep going. Dumb. The road is technical, but it ain't that big a deal as to riding it. Other roads in the area are just as challenging, and other roads around the country offer similar/greater challenges.