What if the two do not agree on a goal? Or, When one participant does not respond affirmatively to (or at all) to the goal of the other, how should the advisor ask if they approve / agree?

Part of what you are looking for in Ideal Clients is that they are respectful with each other during the Financial Road Map™ interview.  Let them work it out and / or ask expanding and clarifying questions to help. One sign that a couple is an Ideal Client is their ability to work through disagreements in a constructive manner and come to a conclusion.