Just had a top laner int feed after getting his lane swapped during autofill

Some random guy got autofilled to support and said he was gonna troll if he didn't get top,our top gave him his lane but ingame he died to first blood and then said gg and started running to my team's lanes and getting killed to turret and enemy team on purpose,then said he didn't care because all he had to do was then get on his main and my team had to open mid and match ended at 10 minutes

So can someone please explain to me why the fvck is nothing gonna happen to him even with reports?