There is a modern-day archaeological discovery that ties in with Elves and proves they did exist (in the manner of finding King Tut or Richard III). Of course, there still a few elves still living... somewhere. They're just super-talented at not being noticed. Maybe Elladan and Elrohir chose to be elves but didn't want to leave. Perhaps Thranduil and some of the others didn't want to leave his/their home either. There's always a chance that Gildor and his people decided not to sail at the last minute. (Setting can be writer's choice but suggest using http:// lotr. wikia .com /wiki/Europe as a guide.)