You're downvoting me for not knowing how to use the app when I bothered to take the time to give you an explanation without any snark? What a nice individual you are.

I went to RIF because I also have it downloaded and to see the linked post in RIF, click at the top and in the box that appears, select "View original at /r/ThatsInsane".

I don't know why people like the RIF app so much, but then I really don't know why people use it and complain to others that they can't view the same stuff. It works fine in the official reddit app.