Add the cheeses, chilies, tomatoes, pickles, ketchup, mustard and Worcestershire sauce to a bowl and combine well. It's not going to look too appetizing at this point, but trust me, the end result is delicious.
Transfer the mixture to an 8" or 9” baking dish and place it in the preheated oven. Cook for 10 minutes to melt the cheeses.
Meanwhile, heat a skillet over medium heat on the stove. Add the ground bison and cook until fully browned - about 5 minutes. Break into small chunks as it cooks.
Remove the cheese mixture from the oven, add the ground bison and stir well. Place it back in the oven for another 10 to 15 minutes or until the dip is hot and bubbly.
Let cool for a few minutes before serving as it will be very hot. Top the dip with green onions and bacon bits. Serve with tortilla chips, pita chips, crackers, crusty bread etc.