For the grits:
Melt the butter in a saucepan, and add garlic and scallions, cooking them until they become tender. Stir in the grits, and toast lightly in the pan, then add the cooking liquid from the lobster and simmer until the grits are cooked, about 20 minutes. (The grits should be fluffy.)
While the grits are cooking, cook bacon in a large skillet until crispy and golden brown, then remove to paper toweling to drain. Pour off most of the fat from the pan. To the same pan which now has a coating of bacon fat, add the mushrooms, onion, garlic, thyme, tomatoes, and parsley. Cook for 2 to 3 minutes to integrate flavors, then return bacon pieces to pan and add white wine. Let wine reduce by half while grits are cooking.
To finish, gently fold lobster, lime juice, and Parmesan into grits. Season with salt and pepper, as needed. Transfer lobster grits to serving dish and spoon mushroom wine sauce around. Garnish with parsley and lemon wedges.