HDHomeRun acts as a UPnP AV server, but it's a "dumb" one just offering the streams -- it doesn't implement the Tuner or EPG extensions. (Which isn't a big surprise, as the company offers an add-on EPG service via subscription -- though you don't need a subscription to just watch/listen live.)

There's also a dedicated client library you can use, instead of UPnP; I haven't played with that yet, so I don't know whether you can just tune it to channel 0x12 and get the raw DVB-T EPG.

Peter