For your tap-learning pleasure I have made instructional videos for each section of the Audition dance. They are posted on YouTube as well as being embedded below. If these are helpful, I will look at creating them for all of the major dance numbers.
The mistake is still in this section, but I wanted the video available to you over break. In the second echo part - shuffle heel toe heel step - the step should be followed by another heel on the right and a step on the left. I missed those for some reason when filming the video. Just add those on to that section and you'll have it. The other parts of Echo were fine.