My mistake, I originally saw older posts displaying random images. Who knows, as they are old, which image was upload first. For now, the line of code calling for the slide works fine.
To bring anyone else up to speed:
I currently using the Yoast SEO plugin which handles the basic Facebook Open Graph functions and in jets the basic metadata into the head call. I simply the below line of code from Dude:
<meta property="og:image" content="<?php echo wp_get_attachment_thumb_url( $slides[0]['slideshow_image'] ) ?>" />
To the header.php file right after this line of code:
<?php
/* Always have wp_head() just before the closing </head>
* tag of your theme, or you will break many plugins, which
* generally use this hook to add elements to <head> such
* as styles, scripts, and meta tags.
*/
wp_head();
?>
The end result, probably considered sloppy, works perfectly fine as long as the SEO plugin is active.
Thank you to both Dude and Kriesi for their efforts on this.