First try --format=bestaudio, if that fails try --format=best and if that fails as well, just pass the URL as-is to VLC. Very fault tolerant and silently ignores errors (except for letting it show up in the logs)...
- TS3Bot is able to play any link that VLC supports via the "play" command, just add any URI as an argument to that command.
- TS3Bot is able to stop the currently playing media via the "stop" command.
- TS3Bot is able to change its own nickname via the "changenick" command.