Using rtMedia, you should be properly able to upload media of types mentioned here - https://rtmedia.io/docs/settings/types/
For any other video types, you can use the Transcoder service or FFMPEG plugin.
Please, share more details on which video type you are trying to upload and what error do you get while playing.
If possible, share some screenshot or website URL so that we can look into the issue.
If you want to get more details on other plugin's functionality, you may visit below reference links.
Transcoder - https://rtmedia.io/transcoder/
FFMPEG - https://rtmedia.io/products/rtmedia-ffmpeg-addon/