So sorry for your loss. If you keep the body cold on ice in a cooler wrapped in plastic bags, you could take it in for a necropsy on Monday. Some do their own necropsies at home, where you could look at the organs for any signs of coccidiosis. Post any pictures of organs here. They can sometimes still get it even if vaccinated. If needed, this is a good video of the organs for identification during a necropsy: