I think cryptocurrencies need a strong PR team for crisis management plans. Who knows, maybe if they had responded to the scandal in time, it would have died down and everyone would have realised that it was #Fakenews and the dude wasn't in fact died or in a car crash. But as time went by, it reached more and more people and they all freaked out and reacted the way they did. As a result, it went sliding down by 20%. Which in my opinion, is A LOT!
The death of the developer (true or not) would have not affected the prices of ethereum anyway. It was because people just realized that Ethereum developers hold shit tons of Ethereum that it is ridiculous to even be holding one now. As Vitalik and his posies hold majority of all Ethereum which means the investors of ethereum just basically handed them billions of dollars.