Not sure it will help but i noticed in the RetroPie Setup that there was a driver section from which you could install XBox and XBox360 driver. I also use a XBox 360 wired controller but on a Pi 3 model B and i didn't have to install that driver. I just know it's there so you might want to try, we never know.
Also i don't know about pre made SD images but i sometime hear people saying that some unexplained issues may occur on pre-installed systems, and would recommend users to install RetroPie manually usuing the official download.
That's all i have. Hope it helps.