Sorry to offer only a guess. I'm guessing that is one of the screw and its subsequent flange of one of the dial wheels on the top left or top right of the controls (gimbal control, etc.) Do either of the wheels fell loose or maybe sinking into the controller? I would save those. If I am correct, the might be repairable with some epoxy or crazy glue, etc., That screw will never tighten like before but it might be snug enough. If that controller landed one of its corner (one of the wheel buttons), my guess gains in probability.
Hope this is fixable. Opening up your controller is not as terrifying as it might sound but it is the only way to definitively identify the breakage.
I'm sure the wonderful braintrust here will chime in with more of an experienced notion.
Good luck ...