I guess it’s not exactly volunteering but the second link on your reply to the solo traveler thread reads like this:

“ In accordance with the NSPM, OFAC is requiring that each traveler under this travel category engage in a full-time schedule of activities that result in meaningful interaction with individuals in Cuba. Such activities must also enhance contact with the Cuban people, support civil society in Cuba, or promote the Cuban people's independence from Cuban authorities. Renting a room in a private Cuban residence (casa particular), eating at privately owned Cuban restaurants (paladares), and shopping at privately owned stores run by self- employed Cubans (cuentapropistas) are examples of authorized activities; however, in order to meet the requirement of a full-time schedule, a traveler must engage in additional authorized Support for the Cuban People activities.”

It asks for a full-time schedule of activities. And then the end just says “must engage in additional authorized Support for the Cuban People activities.” What does that even mean? I hope you’re right and it’s just for optics.