Plugin Not working with Theme?

I am currently using this plugin: https://wordpress.org/plugins/featured-image-from-url/

I am using this plugin on this particular page:http://animebusters.org/ab/dragon-ball-super-quick-summary/

When I use this great plugin it does not work on any of my posts or pages and does not show up as the featured image. I really want to get rid of and COMPLETELY stop using the defaulf wordpress media library to host my files. If you guys can help figure out why this plugin is not working on my theme that would be great. I have granted you guys access so you all can go on in and have a look Thanks so much!