I'd pay cash for the transatlantic part and if the airplane is A330 or A340 use an AF economy reward from CDG to DLA or NSI.
Econo is OK with larger planes on AF. A300/310 series to Cameroon suck for space in econo and I'd try to use the extra miles saved from not using them on the trans-Atlantic for a business class ticket on AF from CDG to Cameroon if they use that type of aircraft when your son flies.
[This message has been edited by BlondeBomber (edited 12-27-2001).]