I don't believe it can be done. Microwave pizza is always precooked, and all you are doing is essentially reheating it. It doesn't get hot enough to brown the crust or topping. All you would end up with is a soft-dough mess.
Besides using a regular 500+ degree oven, which is the normal method, you can also cook pizza on an outdoor grill, which is something I'm sure you find there. Grilled pizza has a wonderful, smoky flavor, and the crust will get delightfully crunchy. Use a loose fitting aluminum foil cap to warm the toppings while the crust gets crunchy.
I wouldn't think about making a large pizza, but more along the lines of a small, personal pan size pizza, a size needed to fit the small available charcoal grills.
Take care and be blessed.
"Food is our common ground, a universal experience." - James Beard