Object picking with 3 orthographic cameras and 3 v

I have a WebGl/ThreeJS application, where I have 3 WebGL Renderers, 1 Scene and 1 Canvas for each renderer. The first 2 Canvases are ok, they work fine.

The other canvas, is divided in 3 equal-dimension viewports and in each viewport I have added an orthographic camera in a different position.

So I want to be able to detect mouse events on the objects that there in this Scene. I want to detect them in all of the viewports independently. All this, because I want to create a drag and drop functionality of some spheres I have in it.

I create my orthographic cameras as the above code giving 3 different positions for eachcamera (12 ,0,0) (0, 12,0) (0,0, 12) and giving the width,height of the viewport (not the canvas) :

    var viewSize = 50 ;
    var aspectRatio = width/height;
    var camera = new THREE.OrthographicCamera( viewSize*aspectRatio / - 2, viewSize*aspectRatio / 2, viewSize / 2, viewSize / - 2, 0, 100);
    camera.position.set(x,y,z);
    camera.lookAt(new THREE.Vector3(0,0,0) );

After having set up the cameras/viewports, and based on this very usefull post : post ,I created and called 1 time for each viewport/camera this function:

{ 
  var raycaster = new THREE.Raycaster();
  var mouse = new THREE.Vector2();

  function MouseEvents( spheres, func, _camera, domElement ) {
    this.plane = {'object3d' : undefined} ;
    this.camera = _camera;
    this.container = domElement; 
    this.objects = spheres;

    var _this =this;

    this.offset = new THREE.Vector3();
    this.INTERSECTED;
    this.SELECTED;

    if(func === 'dragNdrop'){

      this.plane.object3d = new THREE.Mesh(
        new THREE.PlaneBufferGeometry( 10000, 10000, 2, 2 ),
        new THREE.MeshBasicMaterial( { color: "#"+((1<<24)*Math.random()|0).toString(16)  } )
      );
      this.plane.object3d.visible = true;
      if(this.container === 'motifPosX' ) this.plane.object3d.position.z = -100;
      if(this.container === 'motifPosY' ) this.plane.object3d.position.x = -100;
      if(this.container === 'motifPosZ' ) this.plane.object3d.position.y = -100;

      this.plane.object3d.lookAt(this.camera.position);
      MotifExplorer.add(this.plane);

    }
    var mMoove = this.onDocumentMouseMove.bind(this) ;
    var mDown = this.onDocumentMouseDown.bind(this) ;
    var mUp = this.onDocumentMouseUp.bind(this) ;

    document.getElementById(this.container).addEventListener("mousemove", mMoove, false);
    document.getElementById(this.container).addEventListener("mousedown", mDown, false);
    document.getElementById(this.container).addEventListener("mouseup",   mUp, false);

  }; 

  MouseEvents.prototype.onDocumentMouseMove = function(event){ 
    var _this = this;

    event.preventDefault();

    _this.plane.object3d.lookAt( _this.camera.position );
    mouse.x = ( event.clientX / $('#'+_this.container).width() ) * 2 - 1;
    mouse.y = - ( event.clientY / $('#'+_this.container).height() )* 2 + 1;

    //

    raycaster.setFromCamera( mouse, _this.camera );

    if ( _this.SELECTED ) {

      var intersects = raycaster.intersectObject( _this.plane.object3d );
      _this.SELECTED.position.copy( intersects[ 0 ].point.sub( _this.offset ) );
      return;

    }

    var intersects = raycaster.intersectObjects( _this.getAtoms() );

    if ( intersects.length > 0 &&  intersects[0].object.parent.name ==='atom') {

      if ( _this.INTERSECTED != intersects[0].object.parent ) {

        _this.INTERSECTED = intersects[0].object.parent;

        _this.plane.object3d.position.copy( _this.INTERSECTED.position );

      }

      document.getElementById(_this.container).style.cursor = 'pointer';

    } 
    else {

      _this.INTERSECTED = null;

      document.getElementById(_this.container).style.cursor = 'auto';

    }

  }
  MouseEvents.prototype.onDocumentMouseDown = function(event){  
    var _this =this;

    event.preventDefault();

    raycaster.setFromCamera( mouse, _this.camera );

    var intersects = raycaster.intersectObjects( _this.getAtoms() );

    if ( intersects.length > 0 &&  intersects[0].object.parent.name ==='atom') {

      _this.SELECTED = intersects[0].object.parent;

      var intersects = raycaster.intersectObject( _this.plane.object3d );

      _this.offset.copy( intersects[ 0 ].point ).sub( _this.plane.object3d.position );

      document.getElementById(_this.container).style.cursor = 'move';

    }

  }
  MouseEvents.prototype.onDocumentMouseUp  = function(event){  
    var _this =this;
    event.preventDefault();

    if ( _this.INTERSECTED ) {

      _this.plane.object3d.position.copy( _this.INTERSECTED.position );

      _this.SELECTED = null;

    }

    document.getElementById(_this.container).style.cursor = 'auto';

  };

  MouseEvents.prototype.getAtoms = function() {  
    var _this = this;
    var objects = []; 
    MotifExplorer.getInstance().object3d.traverse (function (object) {
      if (object.name === 'atom') { 
        for (var i = 0; i < object.children.length; i++) { 
          _this.objects.push(object.children[i]);
        };
      }
    });
    return _this.objects;
  };

  return MouseEvents;

});

So everything works without any errors in the console, but the spheres are not detectable by mouseovering or clicking. I think that something wrong with my set up numbers, mouse coordinates and canvases dimensions.

I want to note that I also has orbitControls set up for each viewport independently, but I have disabled every function except for the scroll-zoom.

Also, when I add a sphere, it is actually detectable by the function if I zoom so much that the sphere is all over the viewport.

I can't make a jsfiddle because of the complexity and the quantity of the code so I attach this image just to give you an idea: It is a very specific problem so thanks to anyone who at least tries to help me!

I forgot to say that for 1 renderer/camera/canvas that fits to the whole screen I was able to make a draggable sphere. My problem is what do i have to change for having this functionality in a canvas with specific dimensions and for its 3 viewports/cameras.