Ok just in case anybody else runs into this, I've contacted moderates and they gave me the list of info they need to port the VoIP number and it doesn't contain the password.
The form is probably outdated or it's also used for landline numbers that have pins. The list does contain the account number which is not in the form.
So my advice for it is either fill it in with all the info you have, leave the password blank and put your account number on comments (indicating it's the account number) and hope it goes true (wait by the alternative number you provided) or do the safer thing (which I highly advise) activate your account with temporary password and ask moderators to make transfer for you. They will provide you with the list they need for the transfer and will be able to clarify any ambiguity if any before the transfer is submitted.