You didn’t indicate which of the three Denon and Marantz units you intend to use as the primary receiver, so I can only guess that you’re using the 4300 since it has dual subwoofer outputs. You can send the pre-amp outputs from the 4300 to a pair of inputs on the secondary receiver. Set the secondary unit for “bypass” or “stereo” and use the front-channel speaker connections.
You didn’t mention the model of the Marantz, so it’s impossible for me to compare it to the Denon. Look up the online manuals for your equipment (if you don’t already have copies of them), and go with the one that has at least as much power as the Denon 4300.