I know this is a common belief, but Jagex simply doesn't have the manpower to assign a ton of people to inspect individual cases. 90% of bans are bot buster, 10% are report. They discuss it on the mod forums a lot (irl friend). A lot of the pmods are mad that Jagex doesn't dedicate more resources to catching botters. Chances are, he was IP-flagged, or moved to botting world. Still sucks m8, get fresh IP and try again!