Seems that video media texture seems still not working in standalone game after 4.12.2 hotfix. (up to now)
I have tried to copy and paste the wmv file directly into the folder /Content/Movies. I also tried to recreate media player, media texture n material. It works in the editor but not in standalone game after packaging.
So I followed your link to the forum post and it seems you have resolved the issue? Currently the media player is getting an overhaul due to the number of issues reported with its functionality over the past.
Let me know if you have further questions or need additional assistance.