It's literally "who gets the booster on their team" in Gold IV...
...every game - if I get the booster, great I win. If the other team gets it, not great and they win...
I literally have 3/5 games with one of those players. And no, it's NOT "it just looks this way"... accounts with 100% winrate over 30 games with K6, Hec and Twitch ARE booster accounts.
One day, I hope I meet one of them in real life to... talk, chat, stuff like that... :)