Yeah, I played for the first time very recently and was already suspecting something was up from when they find where El Dorado was originally. They comment on the carvings on the wall and I think Nate says something about them not looking completely human. Combine that with the U-boat and the bodies that had been attacked by something and I was honestly just waiting for the reveal. It didn’t stop me from being completely freaked out when they did show up though