I'll admit I am not an amazing antagonist but the problem isn't my skill.
It's fair when you can win, lol.
The raiders happened to be just too efficient to kill elites and minions??? Can you upload some videos so someone can do an analysis?
I played against 50 something MMR antag while ours were almost the same, and the difficulty was around 50. It was at Weapon from the Past. Minions were easy to kill (2 puches), but they appeared a lot. But Elites took a lot of shots before going down. They went immune to cqc as soon as I got close to them, so it was not easy kill.
At a soloQ, I met Ayana antag at the stage escorting Urugal (I forgot the story name.) Her MMR was higher than ours, so the difficulty dropped to 25. But the game was difficult, and we almost lose Urugal. To me, Elites just did fine and were annoying as always.