For the lobster: Bring a medium pot of water to a boil. Heat an outdoor grill over high heat.
Kill a lobster by splitting the head in half with a large chef's knife. Then split the lobster in half down the middle. Repeat with the other lobster.
Snap the claws off from both lobsters and boil for 5 minutes. Remove and submerge in ice water to stop the cooking. Careful to keep whole, crack the claws and remove from the shell.
Use half of the sunflower oil to brush the meat of each lobster tail half, sprinkle with salt and pepper and grill, flesh-side down, moving as needed, until well-marked and the meat is firm and cooked through, about 4 minutes. Let rest for a minute, pull the meat from the shell so its loose and easy to eat out of the shell, squeeze with lemon juice and keep warm. Meanwhile, brush the claws with the remaining oil and sprinkle with salt and pepper. Grill, until just marked and warmed through, about 1 minute per side. Keep warm.
For the steak and warm mushroom salad: Coat a medium cast-iron skillet with sunflower oil and heat over medium-high. Sprinkle the filet mignons generously with salt and pepper. Sear the steaks until nicely browned, about 3 minutes. Turn the steaks over and add the butter and thyme. Baste the steaks with the butter (to infuse flavor into the steak) and cook until medium-rare, about 3 minutes more. Remove the steak from skillet and allow to rest. Turn the heat down to medium. Add the zucchini, cauliflower and mushrooms and cook, stirring gently, until just about tender, about 3 minutes. Add the tomatoes and spinach and stir gently until the spinach is just wilted. Season with salt and pepper.
Meanwhile, for the lobster sauce: Pour the wine into a small skillet and bring to a simmer over medium-high heat and reduce by about half, remove from the heat and whisk in the butter, a tablespoon at a time, until the sauce is combined and emulsified. Stir in the chives, parsley and thyme. Season with salt and pepper.
Divide the steak and mushroom salad between 2 plates. Add 2 lobster tails halves and claws to each plate and top the lobster with the sauce.