Thanks, I do believe your husband is correct. They offer 1 walking tour, which makes me thing they are meeting you at the pier and you just walk to the Colonial District. They mentions these places:
Along the way, you will pass architect Peter Harrison’s Brick Market Museum, the Old Colony House, the White Horse Tavern, and the Quaker Meeting House. You will also stroll past Touro Synagogue, the oldest synagogue in the country and one of the many sites visited by President George Washington, Thomas Jefferson, and others.
I think we can just go walking on our own. Like you I love to just stay on the ship sometimes.