You can test schema.org video markup using Google's Rich Snippet Testing Tool. The testing tool will extract all schema.org data from your page and display it as Google sees it. You may not always see a result preview even when video markup is found.
Video sitemaps and mRSS
In order to test or submit sitemaps or feeds, you must first add and verify your site in Google Search Console. Make sure that you have verified both the site that contains the sitemap or feed and all of the sites referenced in the sitemap or feed.
To test your video sitemaps or mRSS feeds, go to the sitemaps section of your website in Search Console. Within the sitemaps section, the Test tool will immediately download and validate your sitemap or feed for any problems in the markup.
Once you have tested and corrected your sitemap, you can submit it to Google using the Submit tool in the sitemaps section. Search Console will also display errors in your XML file or video pages after you submit your sitemap or feed. Submitting a broken or erroneous sitemap or feed will not harm your video indexing. Once a corrected sitemap is submitted, it will override video data from prior sitemaps.
It may take some time for your sitemap or feed to be processed. You can see your
sitemap's status in Search Console. You can also perform a site-restricted query, such
[site:google.com] on video.google.com to see if your videos have been indexed.