This is not the best forum for your question. I suggest that you post this picture in the Name That Plant Forum where it is likely to be identified promptly.

Good luck, it's a wonderful looking plant.

Looks like a ginormous plumeria.

Very much Plumeria to me. Not native to Africa: it's a central and South American plant that is widely grown throughout the tropics.

Remember: wearing a flower behind the left ear means you're taken, behind the right ear means you're looking...

Plumeria rubra: http://www.riomoros.com/2011/08/la-plumeria-plumeria-rubra.html

Hi

Did you ever get an ID?? I would guess plumeria also but the location and the growth habit suggest something else . Many do get very large but certainly lack the extensive trunk of your pic. Also I thought Kigali was in a high altitude so generally cooler ?? Anyway very curious as to what it actually is lol gary

CA ARR, for what it is worth, compare with this VIDEO.

Definitely plumeria in the second picture in OP.