Digi+ on rpi3b questions

I have an iqaudio PiDac+ and pibow coupé case, but I’d like to have a optical port integrated with it so I can organise my tv and music streaming on one server.

My tv is LG 4K with optical WiFi and Bluetooth audio.

The iqaudio digi+ HAT and additional side extensions obviously made for me.

Do I have to choose between the PiDac and digi or do they both fit to the rpi3b?
Is the digi+ Optical signal from the TV capable of output to the analog rca?
What software is best to manage both lms and tv audio?

I don’t think you can stack them. They are both going to be trying to use i2s and likely share some other pins on the GPIO. You’ll end up with conflicts.
I’m no expert but I don’t think i2s can handle two audio devices like that.
Pi-DAC+ at Raspberry Pi GPIO Pinout
Pi-DigiAMP+ at Raspberry Pi GPIO Pinout

Thanks. I’ll use something like this -an optical to rca adapter to the amplifier. eBay 143445594137
Not a quality adapter but it’s low bit rate audio from the tv.