Those kind words have been said about me, but the one area I've never messed with was using media controllers to send DLNA material to a renderer/player. I have merely used DLNA as a media server on Windows PCs and then used the DLNA-capable apps on the players for playback control.
That said, I'm not certain a Roku device will be seen as a target device from a media renderer. Roku doesn't appear to follow the full DLNA protocol. In the control console of my DLNA server (Serviio), the Roku devices never appear "online", in that Serviio doesn't know for certain if the device is actually connected to the network at that moment. Even while a Roku device is playing media from the server, it still shows as "unknown" connection, although the console does show the media is playing. So some sort of expected communications isn't occurring per the DLNA protocol.
Dan
Roku Community Streaming Expert
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