If you absolutely cannot get to the Vital Records office in Pago Pago, AS, I suggest calling the Vital Records *again* and asking for the supervisor or someone "in charge".
In your most pleasant voice *possible* tell them what it is you are requesting, why, and that you are calling from NZ.
Be ready to FAX your ID and whatever they will request of you also. Please ask them how soon your transaction can be expedited.
Because when all is done they can FAX all documents to you at whatever address you have given. It has been done for me.
Be patient & kind also.