This is probably the "rising" route from Kigali

I wonder which are the most popular destinations from & to Kigali, because in the Kigali-Cairo-rest of the world leg, there are few choices of "direct" connecting in Cairo. There are the second flights of the day at the end of the day to LHR and CDG operated by Egyptair and connecting to hhe Middle East.
About the Star Alliance, there are flights at the end of the day or the beginning of the evening on VIE with Austrian, Athens with Aegean (but an arrival at ATH late in the evening, therefore no connection to ATH) and a flight from LH on FRA which leaves at 4:45 p.m., 3 times a week. Then Turkish Airlines and Ethiopian thanks to the code share with Egytpair on ADD-KGL
These are the main alternatives to then go to Asia, Europe or North America. But the airline has found its market. By the way, Kigali and Cairo were linked in the past by Air France and La Sabena, but I don't know if they could sell tickets between these 2 cities