Getting gold-challenger players in bronze flex?

Notice how I put gold to challenger. I would provide the link however it was a couple months ago so it would be hard to find. One of my friends played against a challenger katarina and the only reason they lost was because she was support. Recently I started to look up my games in lolnexus just to see what I was matched against, and I've noticed that every single game there is always at least one person on the enemy team whole ranks above me. Keep in mind this is bronze and I'm getting matched against plat 5 solo players. That's absolutely ridiculous.

Just off the top of my head I can think of high elo players losing every single flex match with their friends and purposefully placing in bronze, then boosting some of their friends by stomping on lowly bronze players such as myself. Since it doesn't effect their solo mmr, they can do this as long as they don't care about their flex mmr and it's easy to place low in the first place. Sure flex requires a thinking that differs from solo, however these players got to plat somehow, and judging by how they're the only reason I lose sometimes it wasn't from boosting. It could also work as a kind of smurfing, without having to go through the trouble of creating a new account, leveling, buying runes and such, etc.

I'd also like other people to keep in mind that some players only got to higher elo playing one champion, making them noticably worse at others and that is what they could be using in flex. Just wanted to leave that out there.