I think it's Kaiten. Inventing a new move for Hinata in a filler seems far-fetched. Also, it's fully plausible that Neji just said "What was that move?" because he was surprised.

After all, Neji seems to know a hell of a lot about the Main House jutsus. For Hinata to know a move that Neji doesn't know of... NO.

Then again, it is filler...