New client or a DC hack?

So I just played a game and we were winning af. In one moment, 3 players in my team (the strongest ones, btw) including me DCed at the same time. Enemy team took 4 turrets off of that and we couldn't reach their massive lead, when we rejoined. I'm asking if it was an issue with the New client, or if some of them used a DC hack.

I checked the players from the enemy team. One has 74% winrate, but is Bronze 4, which seems pretty suspicious.