Your best bet, as noted is to use AA miles and thus your husband must do a mileage run, or you shoud get an affinity credit card and run $20K of charges through it to get the miles needed -- or less if there is a start up bonus that you get up front.

However, even with the slump in travel, the biggest problem may be getting two seats in award category since you have no elite status with AA, and thus no hope at priority. It is rather late to book this route for January, since it is one of the most popular awards and QF is quite stingy at releasing seats to AA. Also, Business Class seats are in greater demand for paid travel than even First and Coach, so there will be fewer up for award use. That is also why CX might be your best bet. They have experienced greater drop-off and have been putting a higher percentage of seats on award status. Though Business will still be in demand for revenue travel.

There is no way toconvert the UA miles to AA, since AA doesn't participate in the HHonors "laundry", and any other way leaves you with too few miles.

But all this might be academic if no award seats are available. Have you called AA to check availability on either QF or CX? I would do that now if you have not. Then work on getting your husband enough miles since the clock is really ticking away.