I've been experimenting with some of these moves and found some interesting details.
Only




put her in a proper crouching state. This is important because only these are guaranteed to go under all highs (frame advantage/disadvantage permitting).
The rest keep her in a standing state but her "hitbox" shrinks down a bit. Since she doesn't go into a proper crouching state, these moves are not guaranteed to go under all highs.
Which highs get crushed seems to be character specific. I went into practice mode and set the com action to GUARD ALL and the com reaction to HIGH PUNCH. I then threw a simple

and attempted to crush the com's retaliatory jab with


,



and


. I should point out that I buffered



, i.e., it wasn't preceded by a crouch dash.
In cases where the com was controlling a tall character or a character with a high fighting stance (e.g., Jann Lee) all three moves would reliably crush the retaliatory jab. By contrast, in cases where the com was controlling a short character or a character with a low fighting stance (e.g., Kokoro) all three moves consistently failed to go under the retaliatory jab. Still in other cases, only one or two of the three moves in question would crush.
The results didn't seem to hold any correlation with stance (open or closed) or frame disadvantage. It all appeared to be related to the trajectory of the jab of the character the com was controlling. Helena isn't particularly tall but her jab follows an upward arcing trajectory and the end result was that Hitomi could reliably crush with all the three moves I was testing. Kokoro, on the other hand, is short, fights from a low, wide stance and throws her jab from below shoulder level in a slightly upward trajectory which, predictably, resulted in all three moves I was testing getting interrupted.
I found another interesting coincidence while I was testing the above. There are certain moves that push the opponent back quite a bit on block.



,


,


and


are some of them but there might be more. What's interesting 'bout these is that if they are blocked then a


afterwards will reliably crush any retaliatory jab. I suspect this happens 'cause the moves in question push the opponent either just a tiny bit beyond jab range or to the very edge of jab max range and the animation of


has Hitomi ever so slightly moving her head backward before swinging her fist. It works against jabs from every character... except Pai XD. Pai's jab is 11 frames (corrected)/9 frames (in-game info) and has waaay too much range. I hate you, Pai... j/k

.