Send password reset email to primary email address?

My mother's apple ID got hacked recently. The hacker changed her password and rescue email address (previously empty).

The only way she can reset her password is

• Reset password using "rescue" email (apparently owned by hacker)
• Security question (she forgot two answers out of three)

So we are stuck here.

I wonder if there is any way we can reset password using "primary" email (the apple ID email) in this case? She still have access to that email box.