Did you ever find a super-pig provider? If not, I have a connection for setting up an import. I am not ready to do so, so someone who IS immediately interested would be helpful. As to the whole poop thing. A lot of species are naturally carpophagous. More to the point GP poop is essentially similar to fish pellets so some people have taken to hanging their cages over aquaponic fish tanks to create and "easy feed" stack.
Hogs have been used for poop disposal for millenia, since they are omnivorous. That does create that nasty zoonotic parasite cycle, but they are so notorious for it that even today, when modern practices have almost eliminated that in commercial pork, nobody will eat pork rare. Still, I would compost human or pig poop with Black Soldier Fly or with some other method that gets rid of the disease vector. Herbivore poop is more readily usable and both rabbit and guinea pig can be used right on a garden.