My best guess is that it IS sending it but it is getting caught in a spam filter.  Have you tried a different TO address?  Does that work?
I'd need to debug to find the cause.  The email almost certainly is being sent because the BCC recipient gets a copy.  Does the TO field look correct in the BCC copy?
If you add that email address as a BCC or CC recipient does it then get the email?
If you give me FTP access I can debug further.


