How do I get to know if visa is approved or rejected when applying through IWP

[dark angel]

I applied for my sons B1/B2 visa on July 18th at VFS through the child IWP. How do I get to know if the visa has been approved or rejected, coz during personal interview the applicant is told upfront after the interview if his visa is approved. I checked the status on the VFS website and it says "Your passport is under process at the US embassy/consulate". VFS only took my basic documents like my sons passport, fee receipt, barcode and my visa copy, and none of the supporting documents like purpose of the trip etc. They said that if the consulate asks for more documents then I'll need to provide them. In this case how would I be informed if any supporting documents are needed. When I sms VISA US passport# to 57333 I get the message "No records found. kindly check your passport number". But when I track the passport over VFS website, it says "Your passport is under process..." Why is this disprecancy in the status between VFS website and the SMS.
Thanks

[immihelp]

You just need to keep checking with VFs regarding the status.