Matchmaking has a clear issue

I went against an Irelia who had Klepto and ended with a 0-10 score. Bad game, right? Wrong

This person, who is ranked bronze 3 with a 40% winrate, somehow got placed against a gold 4 (me) who has a 50% winrate. They go negative almost every game.

I can't prove this next one with 100% certainty, but I think they were premade with their mid laner (also went 0 kills and multiple deaths). They both have match history with each other and a 3rd player. Does being a premade actually allow you into games with gold 4 players while you're at a bronze 3 level?