Mix corn kernels with 1 teaspoon butter, salt, and pepper in a small bowl.
Spread 1/2 teaspoon butter and 1/2 teaspoon mayonnaise over 1 bread slice; flip. Layer honey ham, turkey ham, Lacy Swiss cheese, Amish Swiss cheese, American cheese, and Cheddar cheese on top. Cover with corn mixture, tomato, sweet onion, and green onion. Cover with second slice of bread. Spread remaining 1/2 teaspoon butter and 1/2 teaspoon mayonnaise on the outside.
Preheat a skillet over medium-low heat. Cook sandwich until cheeses melt and bread turns golden brown, about 6 minutes per side.