How to create nested ember route when each parent has same child ids?

I am using ember-cli from a rails api to try and display the lecture template of a nested route. This is my router:

Router.map(function() {
  this.route('home');
  this.resource('courses', function() {
      this.resource('course', { path: '/:course_id' }, function() {
        this.resource('lecture', { path: '/lecture/:lecture_id' });
      });
    });
});

I have no trouble displaying individual lectures in a course template using:

{{#each lecture in lectures}}
  {{#link-to 'lecture' lecture classNames='list-group-item'}}{{lecture.name}}{{/link-to}}
{{/each}}

So I can see in the ember inspector that my courses and lecture data loads with no troubles. The problem is that when I click on that link, it displays the right URL up top but the page doesn't change.

Course Model:

export default DS.Model.extend({
    name: DS.attr('string'),
    lectures: DS.hasMany('lecture',  {async: true})
});

Lecture Model:

export default DS.Model.extend({
    name: DS.attr('string'),
    level: DS.attr('string'),
    course: DS.belongsTo('course')
});

My ideal scenario would be for the route to point to the level parameter since each course can have lecture levels 1-8, but I am not sure how to even get it to display the ember id because this route does not work:

Lecture Route:

import Ember from 'ember';

export default Ember.Route.extend({
    model: function(params) {
        return this.store.find('lecture', params.lecture_id);
    }
});

Can anyone give me guidance on how to make this nested ember route possible? Thanks so much!