Load 3D object with ofxAssimpModelLoader into the ofxcv face follow example

I want to load a 3D object(stl file) into the ofxcv face follow example. It’s an iron man mask and ideally I want it to follow the person’s face captured from the webcam. The mask shows up fine when I load it using the ofxAssimpModelLoader addon, but when I add into the face follow example, it does not show up at all. Here is my code:

#include "ofApp.h"

using namespace ofxCv;
using namespace cv;

void ofApp::setup() {
    model.loadModel("iron_mask_onepiece.stl");
    model.enableTextures();


ofSetVerticalSync(true);
ofSetFrameRate(120);
finder.setup("haarcascade_frontalface_alt2.xml");
finder.setPreset(ObjectFinder::Fast);
finder.getTracker().setSmoothingRate(0.3);
cam.initGrabber(640, 480);
ofEnableAlphaBlending();
 }

 void ofApp::update() {
    cam.update();
    if(cam.isFrameNew()) {
	finder.update(cam);
    }
}

void ofApp::draw() {
    cam.draw(0, 0);

for(int i = 0; i < finder.size(); i++) {
	ofRectangle object = finder.getObjectSmoothed(i);
	ofPushMatrix();
	ofTranslate(ofGetWidth(), ofGetHeight() , 0);
    //ofSetColor(100, 0, 0, 0);
  //  model.setScale(.5, .5,.5);
    model.setRotation(0, 180, 0, 0 , 0);
    model.setRotation(1, 120, 0, 0 , 0);
    model.setRotation(2, 180, 0, 0 , 0);
    model.setPosition(0, 0 , 0);
    model.draw(OF_MESH_POINTS);
	ofPopMatrix();
    
	ofPushMatrix();
	ofTranslate(object.getPosition());
	ofDrawBitmapStringHighlight(ofToString(finder.getLabel(i)), 0, 0);
	ofLine(ofVec2f(), toOf(finder.getVelocity(i)) * 10);
	ofPopMatrix();
    }
}