Unable to get CPM data from Youtube Analytics account

Question

I'm unable to get CPM data from my Youtube reports:

I'm getting:

{
"error": {
"code": 403,
"message": "Forbidden",
"errors": [
      {
        "message": "Forbidden",
        "domain": "global",
        "reason": "forbidden"
      }
    ]
  }
}

I don't even know where to begin to debug this, and I haven't found anything online.

I'm just trying to curl the endpoint, mirroring this: HERE

Notice that once you finish the oauth process, User will see "You do not have permission to execute this method." and the 403

Also, Notice if you remove 'CPM' from the list of metrics, this will work.

---

Example:

curl --header "Authorization: Bearer _____access_token____" -e "https://developers.google.com" https://content-youtubeanalytics.googleapis.com/v2/reports\?endDate\=2014-06-30\&ids\=channel%3D%3DMINE\&metrics\=cpm\&startDate\=2014-05-01\&key\=_____api_key____

I'm getting the refresh token via:

<script>
var auth2;
var SCOPE = ['https://www.googleapis.com/auth/adwords',
  'https://www.googleapis.com/auth/yt-analytics.readonly', 
  'https://www.googleapis.com/auth/youtube', 
  'https://www.googleapis.com/auth/yt-analytics-monetary.readonly',
  'https://www.googleapis.com/auth/youtubepartner-channel-audit',
  'https://www.googleapis.com/auth/youtubepartner',
  'https://www.googleapis.com/auth/youtube.readonly',
  ] ;

function initClient() {
  auth2 = gapi.auth2.init({
    'clientId': 'my-client-id',
    'scope': SCOPE.join(' '),
    'prompt': 'consent',
  })
}

function handleClientLoad() {
  gapi.load('auth2', initClient);
}
</script>
<script async defer src="https://apis.google.com/js/api.js"
  onload="this.onload=function(){};handleClientLoad()"
  onreadystatechange="if (this.readyState === 'complete') this.onload()">
</script>

the access token I'm using is from the refresh token via:

https://www.googleapis.com/oauth2/v4/token?client_id={my_client_id}&client_secret={my_client_secret}&refresh_token={my_refresh_token}&grant_type=refresh_token

and I'm getting:

{
 "access_token": "ya29.GlvyBZVPpC.....",
 "token_type": "Bearer",
 "expires_in": 3600,
 "scope": "https://www.googleapis.com/auth/youtubepartner https://www.googleapis.com/auth/userinfo.profile https://www.googleapis.com/auth/adwords https://www.googleapis.com/auth/youtube https://www.googleapis.com/auth/plus.me https://www.googleapis.com/auth/youtube.readonly https://www.googleapis.com/auth/userinfo.email https://www.googleapis.com/auth/yt-analytics.readonly https://www.googleapis.com/auth/yt-analytics-monetary.readonly",
 "id_token": "eyJhbGciOiJSUz...."
}

I don't believe it's an issue with my scopes as I am not getting a 403 like:

{
  "error": {
    "code": 403,
    "message": "Request had insufficient authentication scopes.",
    "errors": [
      {
        "message": "Request had insufficient authentication scopes.",
        "domain": "global",
        "reason": "forbidden"
      }
    ],
    "status": "PERMISSION_DENIED"
  }
}