Your welcome
The Embassy is "supposed" to send an acknowledgement letter and this would contain the B File number. Haiti does not seem to follow this protocol and seeing as they rarely respond to people's emails it's hard to get the B File number. I know Castro mentioned they did email her husband but I don't think they email everyone (if an email was provided).
I posted in another thread that if you look on other Embassy's websites you will see that they may indicate a letter will be sent out and advise how much time you should wait before contacting them. I would assume this to mean they would actually respond to you and give you the requested B File number.