Well for one, that post is well over a year old. A little under a year ago, facebook changed the URL of all facebook photos. That post is old so yeah it doesnt exist anymore. If you see that, it usually means the link is an invalid image url. Has nothing to do with you (most of the time).
If you really want to find out, you can "right click" > "copy image url" and paste it in a new tab to see what the link is. Logic should guide you from there as to why you can or cant see it.