Show thumbnails for video media in fancybox with thumbnail helper?

I am using fancybox and have a lightbox with video and stills. My thumbnail helper only shows black thumbs for my videos. I like the thumbnail helper in general, but I need the videos to also have thumbnails if I'm going to keep it. Does anyone know how to make this work? Here is the page for reference: www.staceystormes.com. Thanks so much in advance! =)