Since when were Queen Beryl's henchmen called the shitennou? I've never heard that name before. Anyway, I would definitely go with them. I always found it odd that Jadeite never met any of the others. Though, all four were shown in the same shot in a flasrabroadack.
You could say that about practically any season. For instance, the four sisters in R were extremely minor characters in the manga. I think they only lasted one issue, yet the anime gave them a large arc. The Amazoness Quartet had Sailor Senshi forms in the manga that were also ignored in the anime. The villains in the anime were generally much sillier than those in the manga, etc. Complaining that Sailor Stars isn't accurate to the manga is a little ridiculous considering that none of the seasons were accurate to the manga.
You could say that about practically any season. For instance, the four sisters in R were extremely minor characters in the manga. I think they only lasted one issue, yet the anime gave them a large arc. The Amazoness Quartet had Sailor Senshi forms in the manga that were also ignored in the anime. The villains in the anime were generally much sillier than those in the manga, etc. Complaining that Sailor Stars isn't accurate to the manga is a little ridiculous considering that none of the seasons were accurate to the manga.