Which mistakes?
Räikkönen was taking part yesterday in a show event for Red Bull, the guys who are still paying him until December 31st.
As a matter of fact, originally, he was supposed to take part yesterday in the Bercy karting event (where Grosjean was, BTW) and cancelled it.
Yesterday's was not a crazy snowmobile race between the trees in the forest, but a show event where they have famous sportmen (Timo Scheider, Heidfeld, Klien, etc were there yesterday) and celebrities (singers, comedians,...) in a snow circuit. It's not such a risky thing, it really isn't. It was not what people first think about when told about a "snowmobile race".
Räikkönen was simply unlucky: the Austrian press says it was a pretty harmless incident but Kimi put the hand on the ground in a slightly wrong position, nothing else, just bad luck. He got a little bandage to his wrist and that's all.