If you can do at least some UPnP operations, there is nothing wrong with your network.
Capability of browsing DMS (aka UPnP pull) does not imply a capability of receiving commanded content from DMS/DMC (aka UPnP push). DMR has a separate set of optional functions for pushing, which may or may not be implemented.
The simplest way of diagnosing is to start DeviceSpy from Intel UPnP Developer Tools (Windows application). That will give you all devices in local network, which do publish some UPnP interfaces. The one you are looking for is
AVTransport (UPnP namespace intentionally omitted). No AVTransport means no push. You should see at least a core function
SetAVTransportURI there. Don't be surprised if some DMR software does not show up at all. Capability of browsing DMS and playing content from it does not require publishing any UPnP interfaces. DMC does not publish any interfaces itself either, it just knows how to operate other UPnP interfaces.
About the lack of push-capable DMR implementations for Android: push means that the software must be capable of sitting there with an open port and just waiting for commands from any DMC. My wild theory is that this somehow doesn't align with what Android applications can or should do. The fact is that i have BubbleUPnP and UPnPPlay myself on my Android and i confirm that neither implement push. You can try the rest of Wiki list and let me know the result :)