Roon uses RAAT as the streaming protocol, not DLNA/UPnP. The Roonies (rightly, IMO) hold DLNA/UPnP in contempt, as set out in this post from a couple of years back, and developed RAAT as the better alternative:
https://community.roonlabs.com/t/whats-wrong-with-upnp/2101/3