ANSWER: Just in case someone googles this and my thread pops up in the search, you CANNOT use your familymobile password despite the fact that the port function says you can, you HAVE TO use the security pin. Once you correctly input the security pin the "we need more info from your provider" banner on your verizon account page will disappear. Only then will the transfer process start. Again, NEED to use the security pin, the account password, despite being an option, will NOT work. 

if you know your family mobile password but forgot your pin you can go to your family mobile account page and hit edit account details and your pin will displayed, unlike your password which will be hidden. No recovery needed.