you keep saying "digging" is out of the question, but I'm not sure we're on the same page.
there is no digging involved. you don't actually turn any dirt. You stick the shovel in the ground about 4-6 inches, wiggle it to make a crevice, push the cable down gently with a wrench, then push the crevice closed with your body weight. I've never timed myself but I think 1 person could do 75-100 feet in an hour. When I do it this way I have to show my customers where I buried cable in case they dig in the future because it's nearly impossible to see. unless your plan is to make your wife do it, why should she care if the end result looks the same as before. where there's a will there's a way.
I don't want to talk you out the 2nd dish and receiver, just saying it's possible to do what you originally asked about. Personally I don't like to mirror signals unless you know exactly what you're getting. If you were to ask me in person I would say get another receiver and run coax instead of cat5. You'd still have to bury cable but wouldn't need a 2nd dish. Then I'd offer to bury it for you, for a small fee of course.