As Per Melio - "In order to request payment via Melio, you would need to do so on Melio - and not through QBO. Bill Pay powered by Melio only syncs with the Expenses page and bills, it does not sync with Invoices." 

Can you please tell me I can verify payments by using my Admin's SSN? instead of the Owner? 

Will you accept the ITIN of an Owner if he does not have SSN?