It seemed at that point like Raava was still hanging around as a conscious companion as opposed to the general spiritual force she later faded into. So I'd wager that it was a mix of some of Wan's groupies and Raava herself explaining what in God's name was going on. Plus, maybe the second Avatar's connection with Wan's life was stronger, since there were only two lives to remember; it's possible the second one picked up right where Wan left off.