display page on website outside of WordPress without 404 error

I am using permalinks. I have pages outside of WordPress on my web server to which I am linking. Unfortunately, although the pages load just fine, I get a 404 error when going to these pages that prevents any JavaScript from running. I am using the Oxygen theme. This is an example of the URL that is giving me trouble:

https://marinaringstrom.com/propertylisting/detail.php?mls_acct=517186&datasource=CAAR+MLS

The query string will be dynamic based on which real estate property the user is looking at.

I want Google maps to display on the page, and I have the code setup, but the map does not display because the JavaScript won’t run because WordPress sees this page as missing.

Can anyone help me with this issue?