Replaced joy-con shell; bungled joystick?

I did a shell replacement on my whole Switch, including the body and both joy-cons. Everything went great except for the right joy-con: I must have screwed up the joystick because now it’s permanently sending “joystick right” anytime it’s connected to my unit. The joystick itself looks just fine, it doesn’t look bent. The only thing I can think of is maybe I screwed up the ribbon cable when I plugged it back into the joy-con circuit board.

Has this happened to anybody else? If so, is there a fix? If not, is there a place I can buy a new joystick assembly for the right joy-con?