A third new switch allows me to choose which output from this side of the room goes to the other wall switch. This one selects between Station 112 or the HDMI output of my Sony DVD Recorder, and goes to the wall switch installed previously which switches between that output or Station 201, then going to the USB capture stick in my PC.
So now this setup is pretty much complete, and without having to unplug or move any cables, and only by pressing these switch buttons, I can direct the output of Station 201 or Station 112 or the DVD recorder to the PC USB capture, and also by pressing buttons, I can switch Stations 201 and 112 to monitor-only output so I don't always need to have the PC capture setup running.