Which Rioter to contact?

I have an odd question and it's about a player on the enemy team. I'm not posting their exact account info because I think it's against the ToS but it's mainly just something I'm wondering about. Basically we had a game where the enemy fed repeatedly, and I checked their match history and the numbers do not add up. I'm wondering if maybe someone stole their account or something? It might just be they snapped or something, but the sheer difference in game stats makes me think something else is going on here. Anyways, I was wondering if maybe there was a staff member I could contact to look into this? Just curious. Thanks for any replies or info that might help.