Facebook story mutiple photos display in newsfeed

Question

I'm working on creating facebook stories for my facebook page app.My requirement is to display activity "I voted for this movie " with images as shown in image

I tried posting through Graph api explorer:

 {"title":"cool","fb:explicitly_shared":true,"url":"http://www.facebook.com/name/app_id","description":"cool place",
"image":[{'url':"http://personal.psu.edu/tao5048/JPG.jpg","user_generated":true},{'url':"http://personal.psu.edu/tao5048/JPG.jpg","user_generated":true}]}

In my activity log : But in friends news feed I'm getting like :

there is nothing like "I voted...." in post.Is anything I'm doing wrong?.

Note: apps is not in sandbox mode. Story is not submitted for approval(Only for testing).

Edit

If I remove "user_generated":true ill get single image(even 2 images uploaded) with proper post.