have you gone through your visa interview at the embassy in Argentina? if not you still have that to do before receiving the visa. NOA2 means the United States has approved your USC fiance's petition (i129-f), the embassy in Argentina still has to approve your visa (K-1).
I would also say not to have a party like that.
the marriage is just a signed piece of paper
you can have the party whenever, AFTER you've signed that paper in the US