Flemming, based on my limited knowledge it looks close! As a teacher, I feel a great method is to make everything a progression. If I were to break it down it might look like something as follows:
1: Bring the whip back 5-10 times, doing nothing more than trying to get the thong to make at least a full 360°. This is to find the exact amount of force required to swing whip
2: Using feedback from 1, practice throwing arm and handle out between a 90°-130° angle out and up at the moment the tip makes the complete arc around the circle. If crack not achieved, this part is not a failure, as we are trying to get a consistent "throw". Do not add any wrist motion so you get accurate feedback what your arm angle is doing
3: Do 1 and 2, while adding wrist "snap" at same angle as arm until satisfactory crack is accomplished.
My favorite saying here is the "KISS Principle: Keep It Simple Stupid." Break it down into the individual parts (I know Robby already does this in his videos well) and make the movement a progression so there's also marked accomplishments within the routine. When something goes wrong, you can more easily trace where in the process the fault is happening.
Just my 2 cents
“Trust your own instinct. Your mistakes might as well be your own, instead of someone else’s.” ~Billy Wilder