S.J.
DO NOT wash the silk tie in the washing machine - it will ruin it.
You should be able to fluff the tie enough to make it presentable - if not, spot clean it or rush it to the cleaners and see if they can help you in such short notice.
Suit style is not as important and what it looks like ON HIM. Once he puts it on, does he look professional? It doesn't sound like you have much option right now, so tell him he looks fabulous and let him wear that confidence to the interview!
Good luck!