I'm having the same issue. I have found & released Tommy from the electric fence and cleared all but the last 14 tiles. Tommy & Lux have disappeared and Dr. Grande cannot be found. According to the video (https://www.youtube.com/watch?v=1ORXi1ePlw4&feature=youtu.be @ 10min), the seagull has disappeared and as the first tiles of the remaining tiles are removed, Dr. Grande, Lux, and Tommy appear. The video doesn't show when/why the seagull moves. Thank you for your help.