It's the installation/(mis)configuration of external codecs that cause this kind of problem, (especially 'Codec Packs'), not sure how a script is going to help you fix it.
FWIW, about the only thing I've found that needs external codecs are either Windows Media Player or you want to use a specific codec with a NLE. All the media players/transcoders/editors I've used, (a lot), don't require any installed, they provide their own libraries or executables.
The last post I mentioned a tool that could help you narrow down the problem.
If you don't want to go that way and it's system-wide then I guess the only other way to get the metadata you want is using a script to parse the files with something like MediaInfo and extract it for display in DOpus.
Getting up to speed with Python + sample script - the example just happens to be for MediaInfo