I think you are right. This year I also have the Silene asterias and it looks the same as the S. orientalis. I was already asking myself what plants I really had. I searched the internet and found out that especially European web pages often show pictures of S. asterias as S. orientalis. I think that's how I made the mistake. I got the seeds as S. orientalis, checked the pictures and thought it was okay.
Thank you for your message.
Don't know how to remove the pictures. Do you know?