These repatriation flights are akin to charter flights.
As the webpage states, they are open progressively for reservations ("au fur et a mesure").
AF717 on 13/4 is supposed to be DSS-CKY-CDG. On 6/4 it was DSS-NKC-CDG. AF might still be trying to handle the previous flights from DSS and see how to apportion seats between DSS pax and CKY pax. What will happen in 6 days might be too early to tell. The flight is zeroed in all classes on EF.
The flight is handled from HQ in Paris, you might be better off calling the French nunber mentioned on the webpage 33 839 77 91.