We'll create fresh WordPress site with Video Metabox AOC installed. You have 20 minutes to test the plugin after that site we'll be deleted.
This plugin aims at providing users the capability to upload video to a post. It uses wp.media js object to open an uploader frame and choose/upload videos. Once the video is selected, it will save the id of uploaded media object in a custom field.
You can use the function aoc_get_post_video($post_id) to retrieve the url of video that has been uploaded to a post. This function accepts the id of post (for which the video is to be fetched) as a parameter.