Can Invisalign Cause Teeth to Push Out?

Invisalign doesn't cause teeth to move in an improper direction. So the answer is no. If her teeth moved too far out its because she needed room on the lower teeth and they will be brought back at the end of treatment. As answered above teeth dont just jump out of your head on their own. The dr either designed it that way or she wasnt done with her treatment.

One of the great things about Invisalign is that the patient and the dentist can view what the final result should be before any treatment is started, using a technique called the ClinCheck. However, not all patients respond to treatment in the same way and sometimes a mid course correction is needed. Most dentists see their patients every 4-6 weeks during Invisalign treatment so that progress can be closed monitored and adjusted as needed.

If teeth were pushed out, it was by design. Teeth don't move accidentally, they just can't. If another person needed to do it over,it was due to poor planning originally.
Sometimes a mid course correction is needed when teeth don't track well, but being pushed in or out is by design.