Popup Builder bypasses WordPress index.php

Popup Builder somehow bypasses the WordPress index.php file, that would normally be invoked when a user enters “advantageboating.com”.
We have a security program that is invoked by a php auto_prepend in php.ini. It is supposed to run before every php script. With the popup disabled, it works fine. The prepend file gets invoked, and determines that it was invoked by the WordPress index.php file. It does it’s thing, then redirects to the index.php.

With the popup enabled,things don’t go so well. The prepend file gets called, but this time from ‘wp-admin/admin-ajax.php’, NOT from index.php. The security program normally puts up a Captcha form, and if the user enters the correct answer, the program redirects him to the calling program (normally index.php) . However the Captcha form never gets displayed and things go downhill from there.
I have tried redirecting to index.php rather than to the wp-admin/admin-ajax.php, but still never see the Captcha form

If I access the web site explicitly calling index.php (advantageboating.com/index.php) everything works just fine. I have temporarily disabled the popup so that our security code works to keep the hackers out. But this isn’t a satisfactory solution, since we would like to be able to use these popups.

Any thoughts?

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