Perhaps you wrote this before American Airlines added more details to the article, but: none of the aircraft crew were aware of what was going on when the plane returned to the gate. The woman in the seat next to the victim lied to the air staff and said she was sick, and only when she had got off the plane did she make her accusation.

The law enforcement agent quickly cleared it up after arriving.

Looks like all the staff here did the best they reasonably could do with the information they were given.