I'm using the Instagram Graph API in a business account, and almost everything works just fine. I have created a WordPress port of the Facebook SDK, and the function that retrieves the media items looks like this (part of a class, the $fb object is already authenticated using the default_access_token in the class constructor):
public function get_media( $business_account_id = '', $limit = 15 ) {
$limit = absint( $limit );
try {
$response = $this->fb->get( "/{$business_account_id}?fields=media.limit({$limit}){media_url,caption,thumbnail_url,permalink}" );
return $response->getDecodedBody();
} …Run Code Online (Sandbox Code Playgroud)