She has an i17 low that's +5 on NH. If anyone played SCV they'd know that's patroklos has a similar move that was +2 on nh, and it's one of if not the best low in the game. This is that except even better.
Well that seems rather useless, you'd be better off just using a PB in that instance.
Have you tried 33p4-shoho yet? Maybe 66k-shoho could work on aerial opponents.
So it's either one of two things: Either 4k grants some special property that lets you shoho, or only the shoho in ONG works in juggles. Next thing I'd try is 4k-shoho after an izuna launch and PL.