You can do something similar by utilizing the
stream name alias module. You can create an entry in your aliasmap.stream.txt file. You can also use the IMediaStreamNameAliasProvider2 by resolving to the appropriate url in resolveStreamAlias.
In IMediaStreamNameAliasProvider2 I was suggesting that you can return a rtmp url to resolve in that event handler. Otherwise you can map a stream name to the full rtmp url in stream name alias as well. There is a stream name passed as a parameter but you can resolve it to a complete url.