This report comes from a jumper on the scene:

That morning 8 of us went up to high ultimate ramp, 4 tracking jumpers, 4 wingsuiters. He exited last, solo wingsuit jump. I did not see his jump, was stashing my gear, only heard the strike. According to eye witnesses at landing (3 Belgian jumpers) he got unstable right after the exit, they did not see if he hit the first positive part, so he probably did not get unstable of hitting the cliff in freefall. Then he was in spin and roll for a long time, he could not fix the position, then he pulled, but too late, he struck the ledge at the 1/3rd of the cliff (down at around 250m level) before canopy inflation. After the strike the canopy opened, and he flew down close to the river, landed on a tree already dead.