Images probably won't help, as I don't understand where the data is coming from, so seeing it there won't help. You are going to need to find or figure out what generated the data and what it outputs it on. I think you may find that what ever machine ed Sheeran has uses two video boards each with an hdmi or vga output to one of the screens and probably two different programs each driving one of those video boards / screens. You will need to duplicate that on the Mac end of things and then the output to the screens on your pedal is just the two hdmi cables (possibly converted to vga if thats the screens you get). The hard part I expect is going to be finding out where the data comes from and getting it to the appropriate hardware on the Mac (and / or getting the appropriate hardware for the Mac if yours doesn't already have two video cards). I'm unlikely to be useful there.
Peter