mpv can render video everywhere, even inside a fucking text terminal! Use --vo=tct argument to render the video into text art. Heck, if you're using Xorg it can even render into another app window!
MPV deserves its own community. It's the only player on windows that can handle DV content. Though the default offering is very minimal and difficult to use. There are some awesome gui projects though
At least on android TV, the latest release candidate for Kodi also finally properly supports DV. So I would expect the same thing to be the case for the windows version
I love this player, wish it was more popular. They should make the installation a bit simpler on Windows, it's a bit weird compared to most programs people download
And even if you can't install it on a locked-down device, there's a portable version, too. Install on any removable media (from another machine, to be fair) and it will run from USB without installation.
Selfhosting an *arr stack with Plex/Jellyfin is the way.
There's also Tdarr for automatic transcoding of videos right after they get downloaded, haven't tried it yet so can't comment.
Did you try to install ffmpeg and run: „ffmpeg -i someFile.fileextension -c:a libmp3lame -c:v libx264 -f mp4 outFile.mp4“ to repair the file. Then you should be able to play it on every device. On windows you can install ffmpeg with winget and on linux for example with apt or on macos with brew.
I trying to think which devices can't run VLC and all I've come up with are a pager and a Blackberry. Does anyone have any idea what he's talking about?