User blog comment:FairyRaven/Fairy Tail Chapter 401: Igneel vs. Acnologia, Review and Commentary/@comment-77.194.131.12-20140922125827/@comment-25111584-20140922141522

There is no indication that the Tartaros members know everything about each other. Saying that E.N.D. is a Flame Demon is a general statement, it's mp true. Macro being able to control corpses to an extent is quite specific, not necessary that Silver knew about it; after all, Kyouka thought Silver was a Demon, remember?