Do his parents know? Seems to me the boy has some anger issues and his parents need to know about them so they can help (hopefully).
The boy needs to understand that he can't just kick whatever he wants, whenever he wants.
Also, he needs to be held accountable and help pay for the vet bill.
Sorry I don't know what to tell you about your girl. I certainly hope she is OK and heals properly. I love Ameracaunas.