Combine eggs, cottage cheese, 1 tablespoon oil, 2 tablespoons chopped parsley, 1 tablespoon lemon juice, capers, and scallion in a medium bowl. Using a potato masher or large fork, mash until a coarse paste forms. Season with salt and pepper.
Toss 2 tablespoons oil, 1 cup parsley leaves, 1 tablespoons lemon juice, tomatoes, and olives in a medium bowl. Season with salt, pepper, and more lemon juice, if desired. Gently fold in tuna (don't overmix; keep it chunky).
Toast bread; rub 1 side with cut end of garlic. Spread egg salad on top of each slice, dividing equally. Top with tuna mixture.
