Using ‘add_rewrite_rule’ with access levels

I am trying to use add_rewrite_rule to manage some data structures that exist outside of WordPress but are stored in the same Database. Here is my rewrite rule for reference:

add_rewrite_rule('^tf/?([^/]*)/?','index.php?tf=true&user-date=$matches[1]','top');

This all works fine with the Pilotpress plugin disabled but as soon as I turn that plugin on it limits the visibility of this page and redirects the logged in users I want to the home page.

Is there a simple way to make this rule work? Failing that we will have to set up a page with the correct template and then use get parameters in the URL string. I’m hoping somebody else has had the same issue or theres a little-known fix from an admin.

Thanks