Please checkout this related thread: https://experienceleaguecommunities.adobe.com/t5/adobe-experience-manager/overlay-clientlibs/qaq-p/183703 

You might want to try Connected Assets Functionality as described here: https://experienceleague.adobe.com/docs/experience-manager-65/assets/using/use-assets-across-connected-assets-instances.html?lang=en

There's a way to update all the expiration dates to a future value by using bulk metadata export-import feature of AEM.You can simply export the expiration column for all assets from a root folder (value prism:expirationDate{{Date}} ), edit the excel file, import to update the changes.Process descri...

Have you checked "Include assets in Subfolders" option? Please try selective columns/properties to check the result once. You might want to clear cache and cookies, also restart the browser once before testing again.

Have you tried playing the video without the dispatcher? Try the page with IP. Also, check the issue with a smaller video first. What happens when you turn off the auto-play, does buffering takes some time still?

It seems the primary type has changed from a file to a folder here. Please click on the folder and check the properties. You can modify the jcr:primaryType=sling:Folder to the correct primaryType by doing a comparison on local setup.Usual types can be:sling:OsgiConfig, dam:Asset etc. Also share the ...

This usually comes up during Adobe outage/maintenance.Please check: https://status.adobe.com/ Also, contact AEM Customer support to get clarity. 

Try a few troubleshooting steps like:1. Uploading this video to another folder path2. Renaming the video3. Try with other videos (if not tried yet)4. More info on 408 error- https://www.lifewire.com/408-request-timeout-2622937