Ultimate Facebook Youtube Thumbnails

My sons golf site has many youtube videos. Just started using facebook plugin, but can not figure out how to get the plugin to push the youtube thumbnail along with the txt from the post.

http://mattpawlygolf.com/2015-us-kids-texas-open-day-2/
https://www.facebook.com/mattpawlygolf

This post has images and video, the plugin took the first image from post (very big version of it)

this post
http://mattpawlygolf.com/saturday-putting-practice-7/
only has a video and has no image.

1. Would like to have images from the youtube videos as the facebook post image.
2. How to, after the post has been put on facebook, to get the plugin to repost to FB with new settings. ( i believe it just says that it has already been posted).

Thanks