My wife and I will need to make two trips to Addis Ababa, Ethiopia (ADD) this year to complete the adoption of a little girl. The adoption costs have been daunting and I am trying to figure out how to maximize my various frequent traveler accounts to reduce (or eliminate) plane fares. Our travel time is unknown, but we expect it could be this summer and fall for the trips. It is not always clear to me how to use FF miles on partner airlines, etc. so any advice from more seasoned travelers would be greatly appreciated. Also if needed we could break up the trips into two segments if using the miles on various programs on the same trip makes any sense. Thank you!

Our particulars:
DL Silver Medallion 240,000 miles
US Air Silver 150,000 miles
AMEX Mem Rewards 300,000 points
HHonors 115,000 points
Hertz 10,000 points