You're correct.
The "Amends" should have been for her to issue a personal, written apology to the teacher and class, to be hand-delivered.
As it is, here's what dear old dad accomplished:
1. He has set himself against his daughter as an enemy, and that's never good.
2. The rest of the class will sympathize with the girl, and she'll no doubt go along with them on the matter.
3. The authorities will be keeping uncomfortably close tabs on dear old dad and mom -- this incident really does suggest the possibility of child abuse at home.