Featured image not showing on page

From the url you supplied it looks like you are using a custom post type of blog. The most likely reasons you are not seeing the post you want to display is that by default WP_Query is only set to display posts – see WordPress Codex on WP_Query Post & Page Parameters for more info.

So for your WP_Query to return the post you are after you will need to replace line 2:

$myblogPosts = new WP_Query('cat=5'); // Cat 5 is the blog category.

With something more like this:

$args = array( 'post_type' => 'blog', 'cat'=> 5); // Cat 5 is the blog category.
$myblogPosts = new WP_Query($args);