Double check that the change to the WA_Universal_Email/MailFormatting_PHP.phpfile is making it up to the server. try deleting the WA_Universal_Email/ folder from the server, then re uploading it.
if that still doesn't work, take the redirect to the thank you page off, change:
and add the following code at line 1:
This will help us see if a PHP error is occurring.
If no php error is occurring and the emails are still not being sent, you may need to contact the host to see if they can take a look in the SMTP server error logs to see why the emails are not being relayed.