He looks like a telescope eye to me, but I'm not an expert. The website is just a guide - don't forget goldfish come in so many different colours and varieties, and you may get some that have been crossbred with other types, so you may not get a perfect identity. They also change colour as they get older/get exposed to different conditions, so I wouldn't go on colour as an ID.
The orange fish you see in my avatar used to be pure black, as an illustration.