[Dakota]

As you describe it, it sounds illegal.

Here are the rules that apply (all are ASA):

RULE 1 - THE DEFINITIONS

CROW HOP. (Fast Pitch Only)A crow hop is defined as the act of a pitcher who steps, hops, or drags off the front of the pitcher's plate, replants the pivot foot, establishing a second impetus (or starting point), pushes off from the newly established starting point and completes the delivery.

LEAPING. (Fast Pitch Only) An act by the pitcher which causes the pitcher to be airborne on the initial move and push from the pitcher's plate.

RULE 6 - PITCHING REGULATIONS (FAST PITCH)

Section 3. LEGAL DELIVERY.
G. In the act of delivering the ball, the pitcher must take one step with the non-pivot foot simultaneous with the release of the ball. The step must be forward and toward the batter within the 24-inch length of the pitcher's plate. It is not a step if the pitcher slides the pivot foot across the pitcher's plate toward the batter, or if the pivot foot turns or slides in order to push off the pitcher's plate, provided contact is maintained with the plate. Raising the foot off the pitching plate and returning it to the plate creates a rocking motion and is an illegal act.

H. Pushing off with the pivot foot from a place other than the pitcher's plate is illegal. This includes a "crow hop" as defined under Rule 1.

I. Pushing off and dragging the pivot foot in contact with the ground is required. If a hole has been created, the pivot foot may drag no higher than the level plane of the ground.

From your description, it sound like she was both leaping and crow hopping. Both are illegal. It doesn't even sound subtle, so I have no explanation as to why the umpire wouldn't call it.