ember not recognizing plural type in payload

application.route.js

import Ember from 'ember';

export default Ember.Route.extend({
  init() {
    this._super(...arguments);
    
    $.mockjax({
      url: '/api/mock',
      responseText: {
        "data":
        	{
        		"id":"2506","type":"order",
       			"attributes":{"paid-amount":"109.29","net-amount-received":"105.0","total-fee-amount":"4.29","paid":true,"payment-method":"Stripe","host-name":"SwingIN 2016","host-url":"//swing.vhost/swingin2016","created-at":"2016-06-19T20:30:53.218-04:00","payment-received-at":"2016-06-19T20:32:01.000-04:00","total-in-cents":10929,"stripe-refunds":[{"amount":2075,"created":1466392180,"status":"succeeded"}],"current-paid-amount":"88.54","current-total-fee-amount":"3.69","current-net-amount-received":"84.85"},
              "relationships":{
              	"order-line-items":{
              		"data":[
              			{"id":"3313","type":"order-line-item"},
              			{"id":"3314","type":"order-line-item"}]},
              	"host":{"data":{"id":"23","type":"events"}},
              	"attendance":{"data":{"id":"1814","type":"event-attendances"}},
              	"pricing-tier":{"data":{"id":"57","type":"pricing-tiers"}}}}
      }
    });
  },
  model() {
    return $.getJSON('/api/mock');
  },
  
  actions: {
    refreshStripe() {
      console.log('action called');
      Ember.$.ajax({
        url: '/api/mock',
        type: 'GET'
      }).then(data => {
        this.get('store').push(data);
      }, error => {
        let json = JSON.parse(error.responseText);
				console.log(json);
      });
    }
	}
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName:'Ember Twiddle'
});

models.attendance.js

import Model from "ember-data/model";
import attr from "ember-data/attr";
import { belongsTo, hasMany } from "ember-data/relationships";

export default Model.extend({
  host: belongsTo('host'),
  orders: hasMany('order')
});

models.event-attendance.js

import Model from "ember-data/model";
import attr from "ember-data/attr";
import { belongsTo, hasMany } from "ember-data/relationships";

import Attendance from './attendance';

export default Model.extend(Attendance, {
});

models.event.js

import Model from "ember-data/model";
import attr from "ember-data/attr";
import { belongsTo, hasMany } from "ember-data/relationships";

import Host from './host';

export default Model.extend(Host, {
});

models.host.js

import Model from "ember-data/model";
import attr from "ember-data/attr";
import { belongsTo, hasMany } from "ember-data/relationships";

export default Model.extend({
  orders: hasMany('orders')
});

models.order-line-item.js

import Model from "ember-data/model";
import attr from "ember-data/attr";
import { belongsTo, hasMany } from "ember-data/relationships";

export default Model.extend({
  order: belongsTo('order')
});

models.order.js

import Model from "ember-data/model";
import attr from "ember-data/attr";
import { belongsTo, hasMany } from "ember-data/relationships";

export default Model.extend({
  host: belongsTo('host', { polymorphic: true }),
  orderLineItems: hasMany('order-line-item'),
  attendance: belongsTo('attendance', { polymorphic: true }),
  pricingTier: belongsTo('pricing-tier'),
});

models.pricing-tier.js

import Model from "ember-data/model";
import attr from "ember-data/attr";
import { belongsTo, hasMany } from "ember-data/relationships";

export default Model.extend({
  orders: hasMany('order'),
  event: belongsTo('event')
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
<br>
<br>
{{model}}

<button {{action 'refreshStripe'}}>Send Ajax</button>

twiddle.json

{
  "version": "0.4.8",
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.6.0",
    "ember-data": "2.6.1",
    "ember-template-compiler": "2.6.0",
    "jquery-mockjax": "https://cdnjs.cloudflare.com/ajax/libs/jquery-mockjax/1.6.2/jquery.mockjax.js"
  }
}