The password algorithm changed in the lasts versions of Whatsapp, at least in iPhone. You can get a Base64 of the md5 from the application directory, but it doesn't match the imei or mac md5. I am trying to break mine with hashcat to see what kind of pattern it follows.
Tried again here, not working. Do you know if it is possible to sniff the iphone connection and get the md5? I have generated the hash from the duplicated mac and want to check that it is identical.
My number is not from the US. Maybe you are creating the JID using the US country code + the phone number field instead of using the full number field?