PHP in Email Settings

Hi

I need to pass PHP variables to HTML email. I have one of two options, 1. manually code it in and use custom HTML email templates, or 2. Use PHP inside the email settings.

Either way, it does not seem to work.

Can someone please point me in the right direction so I can use variables inside the account deactivated email. FYI, the variable is a MySql query (wpdb) inside a custom plugin.

Thanks!