You could get a Sonos Port and connect the RODECaster Pro’s audio out to the Port’s line-in connections, but you would have to get RCA to ¼ adapters to connect an RCA cable to the RODECaster. Then you would just select the Line-In option under Browse in the Sonos app to play the audio from the RODECaster to your Sonos speakers. NOTE: You may experience a very slight audio delay.
FYI… Sonos speakers are designed more for consumers/home audio. I know many churches often operate on a limited budget, but you might consider using pro audio speakers and equipment in the future.
I think the intention was to continue using Sonos as the audio source, but send that audio to the RODECaster? If that’s the case, you would still want to use a a Port, but the line out, not the line in. To the RODECaster’s input of course. In this scenario, you shouldn’t see any audio delay.