-    @classmethod
-    def _transform_rtmp_url(cls, rtmp_video_url):
-        if 'error_not_available.swf' in rtmp_video_url:
-            raise ExtractorError(
-                '%s said: video is not available' % cls.IE_NAME, expected=True)
+    def _extract_mgid(self, webpage):
+        mgid = self._search_regex(
+            r'MTVN\.VIDEO\.contentUri\s*=\s*([\'"])(?P<mgid>.+?)\1',
+            webpage, 'mgid', group='mgid', default=None)
+        if not mgid:
+            mgid = self._extract_triforce_mgid(webpage)
+        return mgid