Any idiot can get lucky and leverage his positions to the max. Please, this is a joke. He got lucky and leveraged it to the max. Bottom line, no way he could ever be consistent with that. On hit wonder.
If he would have ended third with 180%, he would still have a drawdown of more than 75%. So he lost more than 3/4 of his equity end of the first week. That confirms he had luck, if he would have a system the losses would have been much smaller. In every contest there are thousands of participants. So statistically in every contest there will be "traders" with huge returns. Even if it's a contest where only idiots can participate.
Who would trade a demo accoun to possibly make $1000 rather than trade their live account for real $?