The springboard may be the problem because they are meant to help you go up, and that seems to be what she intends to use it for. That's part of the reason I suggested a fold up mat, the other part is that you don't want her to get enough energy from the hurdle to make the round-off an easy proposition.
I came by this drill entirely by accident. This all started because we had to share the floor ex with another group. So I set up a circuit of thee mats at one end of the mat, with three at the other end, and told the kids there would be no more running, and they could get all the energy they needed by working from a 4 inch stack mat. The mat height changed to six inches over the course of time, but pretty much they figured out how to properly work into and out of their round-offs to the extent there were kids doing ro-bhst-1/1 and ro-bhs-bhs-2/1. Once we got the entire mat to ourselves and could run again they maintained all of the disciplined, efficient positions and tumbled like crazy.
You could try it from the mat stack, or give her some object to hurdle past to encourage distance. Another usefull adaptation is to have her not hurdle at all.........
Use the same mat stack starting at two inches, and increase to a maximum of six as she gets used to things. Have her stand with her arms up and body in perfect handstand alingment. She shouild lift her "front leg" to horizontal, pause, and then let herself begin to fall forward. She should let the fall get about to the "scary point" and then transition into a round-off by placing her front foot and kick the back leg hard. This skill should be dominated by her back leg kicking up. Her next focus should be maintaining her handstand alingment, which will give her the best inverted posture possible to get the best block out of the inverted phase.