If you are going to to go the Amex/ANA route, keep in mind that ANA only allows round trip award bookings.
Another option would be to use your father's AA miles to book one way. Sign up for the Chase Sapphire Reserve (one for you and one for your future wife) and transfer to KE for the other direction. They have probably the best availability of any of the options since they allow only very limited access to partners for business/first award seats.