Here is a site that I'm upgrading for one of my clients: http://home.minitraper.pl/
As you can see, rolling the mouse over the facebook icon on the right, the LikeBox panel shows only 2 faces/connections but there are 5 people who like the page. I was playing around with various versions of LikeBox code (the current one is the iframe version) but it didn't change a thing.
What can possibly be wrong?
It could be that these people have set their FB preferences so you cannot be seen here unless you are that person's friend. You can't do anything about this.
This seems the most likely answer.