Yeah, but again it's based on a tweet that the student freely posted, and even if I read the tweet out of the context of the article (which I agree was written to cast the student as a villain) I would have read the tweet as the student bragging that they intentionally hurt a patient for saying something they found personally offensive. If that isn't what the student meant... then they shouldn't have said it.
Yes, it's a professionalism violation, and yes it's possible she could be expelled. She definitely would have been expelled if she, for example, punched the patient in the face, and I'm not sure that just because she harmed the patient in a way that gave her plausible deniability changes the underlying fact that she intentionally harmed a patient.