JrSeamless will not work
Installation and Configuration
Where you have
{jrSeamless_list modules="jrVideo,jrYouTube" order_by="_created DESC" require_image="video_image" limit="16" template="index_video.tpl"}
replace it with
{jrSeamless_list modules="jrVideo,jrYouTube" order_by="_created DESC" limit="16"}
then view the page to see a mix of video and youtube items.
Hint - Set your cache time to 0 (zero) when developing templates so as to see any changes immediately.