The very first viral campaign video shows Chris recieving a medal for his actions in Kijuju. The rest show him being haunted by his memories from Kijuju. And the last one shows Sheva waking him from a flashback and telling him that they have another mission. That could be a hint that they wanted Chris and Sheva back in another game. But these were made before the game was released. I personally wouldn't mind having Sheva back. But I wouldn't want her with me the whole time again. Being alone in the game makes it a lot scarier.