hi maximilien,
i do not know if i can be of help, but try knocking at the national sports council, they should be able to help, i myself need to check when is the seychelles next mini cross country (10km) as i am a trail runner. if you have any dates let me know. i just got to seychelles a week ago, & i need to start running, if you know the roche caiman running trail that's where most people run. maybe i will meet with you some time & we can run together.
regards