I think it's worth highlighting that Ayn Rand was not a proponent of either the Liberatarian Party or the libertarian movement in general. She considered it unprincipled and open to any idea, no matter how fundamentally bankrupt, as long as it was "anti-government." This Chicago Sun-Times story gets it right when it says:
"But what makes Doherty's book a self-described "freewheeling" history are its detailed descriptions of the colorful characters and eccentrics who helped create the libertarian movement. There is novelist Ayn Rand, of course, responsible for recruiting more members to the movement than anyone else even though she disavowed the label, and waged war against many of its proponents. "
It does later call her one of the "founders" of the movement, but I think that wasn't meant to mean that her involvement was intentional. Certainly, many of her ideas feed libertarianism, but only incidentally--and that, in part, is what's wrong with libertarianism.