I partly agree with you but it all happened so quick like in the space of 12 hours
Could it have been a coincidence that a sell off coincided with the bch thing?
or was a selloff planned to coincide with the bch thing to trigger a bigger sell off to manipulate the market down?
that's how every selloff is. in general, price rises slowly and drops fast. an old saying that traders have: "price takes the stairs up but the elevator down".
some larger sellers may have intended for the selloff to coincide with the bcash fork, since there was obviously some confusion around it. but IMO the real reason most people sold is because the price went down, not because of any news.