Good to hear that you continue to read higher-level books to her. If she doesn't like to read for pleasure, don't be afraid to read aloud to her, or use audiobooks. If there is some kind of impairment to fluent, independent reading development, this kind of exposure to higher-level text will help her oral language and vocabulary skills continue to move forward while you and/or her school try to figure out her reading.
The anecdotes about letter names and flashcards tend to support the hypothesis that there is some kind of obstacle to developing automaticity in decoding (orthographic mapping is one of its names).
