I would suggest to reconnect with them by the contact info you have now, and simply tell them that unless they supply you full details about their company:  physical location,  state of business registration (where corp. or llc papers are filed), bank reference, etc., within 48 hours, or otherwise you want your contact info taken out of their system.  You do not want to do business with anyone whom you do not know who they really are, and where they are domiciled.  

As the sex educators say:  "have your protection in place".