@Paul8777 I agree that you should accept this request. It's your bird in the hand.
In the future, you can always manually adjust your calendar settings to set special requirements around holidays. But for now, I wouldn't let down this guest who's taking a big chance on a new listing with only 8 reviews.
Your retreat does look like an awesome place to spend Thanksgiving, but I wouldn't worry about losing out on a booking - most people don't get that whole week off anyway. The day before Thanksgiving is often the busiest flying date in the year in the US because that's when people are rushing off to begin their holidays. As long as you're set for a same-day changeover, you'll be fine.
But your 2-night minimum might be a bit short for a property that size.