As I said, we have WP running on an NGINX server which is replacing an old Joomla server.  The issue has to do with the fact there were several static PHP pages built over the years on the Joomla server that we don't want to move manually to the WP server.  

The problem is that our Marketing used a lot of these standalone .php files in ads and such and want those urls to work by redirecting either to the home page or to specific pages inside WP.  (The latter is not a must have.)

The problem is that I can't figure out a way to have NGINX test for a particular .php file and if it's not there, redirect to (or display) a 404 page inside wordpress.  In every case, when NGINX tries to find that .php file it throws up the NGINX 404 page.  

I can build a custom 404 page, but Marketing wants to use the page inside WP.  There are several configs floating around that appear to solve the problem, but none of them work for me.  I've been told this is possible, but I've not found the answer if its out there.  Someone got any ideas?

I've attached my config file if that will help.

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