I agree with what you are saying, And if she is doing that either staying back or too late then she doesn't under stand sequence of thinking she needs to gain ground or move the mass Early. She simply thinks stay back. I also agree its partly balance as well. The kids that I talk too at her age, which was I'm familiar with require being told steps. Step 1, step 2 etc.
I understand what you are saying. I wouldn’t classify this as a sequencing issue though. The young lady is out of balance which puts her out of sequence. During her load.. balance imo is first,sequence is second. You can’t have a good sequence without balanced actions first and foremost. Make sense?
Once the body is outta balance, compensations occur which will throw the body out of sequence.