Null Object Reference error when coding a custom event (mod-folder)

[MAZ12211]

For context I wanted to create a custom event that rotates the camera with ease effects much like base game
I have no clue what causes this error, I've reread it several times for a missing semicolon but I got nothing
V0.5.3

// Mostly copied from source code lol
import funkin.play.PlayState;
import funkin.Conductor;
import funkin.modding.events.ScriptEvent;
import funkin.modding.module.Module;
import funkin.ui.AtlasText;
import flixel.FlxG;
import flixel.tweens.FlxTween;
import flixel.util.FlxTimer;
import flixel.tweens.FlxEase;
import flixel.FlxCamera;
import funkin.graphics.FunkinSprite;
import funkin.Paths;
import openfl.utils.Assets;
// import Reflect; Had no clue it was blacklisted, so I used ReflectUtil instead
import funkin.util.ReflectUtil;
import funkin.play.event.SongEvent;

class CameraRotateEvent extends SongEvent {
    function new() {
        super("cameraRotateEvent");
    }
    public var DEFAULT_ANGLE:Float = 45.0;
    public var DEFAULT_DURATION:Float = 4.0;
    public var DEFAULT_EASE:String = 'linear';

    public var cameraTween:FlxTween = null;

    public override function handleEvent(data:SongEventData):Void {
        if (PlayState.instance == null || PlayState.instance.currentStage == null) return;
        
        // Does nothing if we are minimal mode.
        if (PlayState.instance.isMinimalMode) return;

        var duration:Float = data.getFloat('duration') != null ? data.getFloat('duration') : DEFAULT_DURATION;
        var toAngle:Float = data.getFloat('angle') != null ? data.getFloat('angle') : DEFAULT_ANGLE;
        var ease:String = data.getString('ease') != null ? data.getString('ease') : DEFAULT_EASE;
        
        switch (ease) {
            case 'INSTANT':
              // Cancel the tween here, so it doesn't tween (haven't tested it yet)
              cameraTween.cancel();
            default:
                var durSeconds = Conductor.instance.stepLengthMs * duration / 1000;
                var easeFunction:Null<Float->Float> = ReflectUtil.getAnonymousField(FlxEase, ease);
        }
        
        rotateCamGame(toAngle, duration, easeFunction);
    }

    public function rotateCamGame(?toAngle:Float, ?duration:Float, ?ease:Null<Float->Float>):Void {
      // Doc says normal tweenning isn't recommended for this case, so I used FlxTween.angle 
      cameraTween = FlxTween.angle(PlayState.instance.camGame, PlayState.instance.camGame.angle, toAngle, duration, {ease: easeFunction});
    }

    public override function getTitle() {
        return 'Camera Rotate';
    }

    public override function getEventSchema()
        {
          return [
            {
              name: 'angle',
              title: 'angle',
              defaultValue: 45.0,
              step: 0.1,
              type: "float",
              units: 'x'
            },
            {
              name: 'duration',
              title: 'Duration',
              defaultValue: 4.0,
              step: 0.5,
              type: "float",
              units: 'steps'
            },
            {
              name: 'ease',
              title: 'Easing Type',
              defaultValue: 'linear',
              type: "enum",
              keys: [
                'Linear' => 'linear',
                'Instant (Ignores Duration)' => 'INSTANT',
                'Sine In' => 'sineIn',
                'Sine Out' => 'sineOut',
                'Sine In/Out' => 'sineInOut',
                'Quad In' => 'quadIn',
                'Quad Out' => 'quadOut',
                'Quad In/Out' => 'quadInOut',
                'Cube In' => 'cubeIn',
                'Cube Out' => 'cubeOut',
                'Cube In/Out' => 'cubeInOut',
                'Quart In' => 'quartIn',
                'Quart Out' => 'quartOut',
                'Quart In/Out' => 'quartInOut',
                'Quint In' => 'quintIn',
                'Quint Out' => 'quintOut',
                'Quint In/Out' => 'quintInOut',
                'Expo In' => 'expoIn',
                'Expo Out' => 'expoOut',
                'Expo In/Out' => 'expoInOut',
                'Smooth Step In' => 'smoothStepIn',
                'Smooth Step Out' => 'smoothStepOut',
                'Smooth Step In/Out' => 'smoothStepInOut',
                'Elastic In' => 'elasticIn',
                'Elastic Out' => 'elasticOut',
                'Elastic In/Out' => 'elasticInOut'
              ]
            }
          ];
        }
}

[KoloInDaCrib]

I think it's cuz you defined easeFunction only in the default case

my proposed changes would be to define easeFunction outside the switch block (with a null value as a start value) and then set it to a value in the default case instead of defining it there

[MAZ12211]

Like this?
While this resolves the error, the event doesn't work in-game at all. no camera rotation at all and no error pop ups too

public override function handleEvent(data:SongEventData):Void {
        if (PlayState.instance == null || PlayState.instance.currentStage == null) return;
        
        // Does nothing if we are minimal mode.
        if (PlayState.instance.isMinimalMode) return;

        var duration:Float = data.getFloat('duration') != null ? data.getFloat('duration') : DEFAULT_DURATION;
        var toAngle:Float = data.getFloat('angle') != null ? data.getFloat('angle') : DEFAULT_ANGLE;
        var ease:String = data.getString('ease') != null ? data.getString('ease') : DEFAULT_EASE;
        var easeFunction:Null<Float->Float> = null;

        switch (ease) {
            case 'INSTANT':
              // Cancel the tween here, so it doesn't tween (haven't tested it yet)
              cameraTween.cancel();
            default:
              var durSeconds = Conductor.instance.stepLengthMs * duration / 1000;
              // var easeFunction:Null<Float->Float> = ReflectUtil.getAnonymousField(FlxEase, ease);
              easeFunction = ReflectUtil.getAnonymousField(FlxEase, ease);
            }
        
        rotateCamGame(toAngle, duration, easeFunction);
    }

    public function rotateCamGame(?toAngle:Float, ?duration:Float, ?ease:Null<Float->Float>):Void {
      // Doc says normal tweenning isn't recommended for this case, so I used FlxTween.angle 
      cameraTween = FlxTween.angle(PlayState.instance.camGame, PlayState.instance.camGame.angle, toAngle, duration, {ease: ease});
    }