OK, it looks like 6A super armor starts 19 frames into the attack. If I'm reading this right: http://www.dustloop.com/wiki/index.php?title=Frame_Data_(Tager_BBCSE)
Haku jump startup is 4 frames, plus the +3 from GF, makes 7 frames. Then Hotaru itself has 11 frames of startup, that's 11 + 7 = 18. So I guess it can work if I Hotaru 1 frame too slow.
EDIT: Oh wait it says 6A starts super armor 18 frames in. A perfect match.