Congrats on expecting, you didn't provide a link to your headphone model: can't really speculate otherwise.
I would advise you to give links to the manufacturer's web site: not an e-commerce web site because you could look like you are advertising for BB.CA. I won't click through to those links.
My only experience with Bluetooth pairing a headset to my PS3 is for multiplayer chat: the audio of movies, games, etc. do not come through. So think of it as a chat channel only, not full audio. Unless you were trying to pair with your Denon AVR? You still might be able to downmix the PS3 to stereo or force the PS3 to output stero, I don't really know what or where the limitation may be. My understanding is that stereo bluetooth requires a profile capability for the headset and the transmitter.