Higher ELO Players Creating ALT Accounts To Specifically Troll

I was playing a ranked match, and before the match started I op.gg a chogath top, and saw that most of his matches were as a ADC. I asked him about it, and he said that he's actually a gold 3 player, and that when you take off the 1 at the end of his username that's his real account. I asked him what he was doing making an alt to play at bronze level, and he said he was just going to have some fun trolling bronzies. Then 3 minutes in, he proceeds to die 3 times, and then claims he's going to start trolling now, and that it doesn't matter if RIOT bans this alt account because he would still have his main. At then end of the match, his score is 3 / 14 / 6, and we lost the match because of that.

I op.gg the account that he claimed that is his main, and saw that indeed, it is gold 3, and mains most of the champs on his alt account. So my question is, can his main account get banned for doing something like this?

ALT: http://na.op.gg/summoner/userName=cjl1agent1 CLAIMS TO BE HIS MAIN: http://na.op.gg/summoner/userName=cjl1agent