I would say your best bet is to use the AA miles. Your 115,000 is more than enough for Qantas (105,000) or Cathay (100,000) biz seats. As an added bonus with Cathay, you get a stopover in Hong Kong. Since your husband is 26,000 miles short, you could do a few things. He could take a mileage run to europe. If you are on the west coast and he doesn't mind making some odd connections, that can be around 7,500 miles each way. That's 15,000 rt. With the double mile promo and the 2,000 online bonus, he can get over 30,000 miles for a few hundred dollars.

Another option is to post in the coupon connection board that you have a lot of united miles. Try to get someone to trade 100,000 AA miles for your husband's 80,000 UA miles.

Whatever you end up doing, call AA NOW and get seat reservations for january. You can always cancel them later, but that's peak time down under and award tix are hard to come by then.