A few things:
The Furrion doesn't seem to be a true AVR receiver (so you can't input video devices through that) - No HDMI input, only the RCA
https://cdn.accentuate.io/1944961089...V3050-V1.4.pdf
You will need to hook up the audio out from the TV (RCA) to an audio input on the back of the Furrion.
RCA video is very poor (300 lines of resolution). You want to avoid that.
I would consider replacing the Furrion, myself.