Force a 403 response to xml file in WordPress

I’m looking to force a 403 access denied response for an xml file in a directory outside of the default WordPress install.

The url I’m trying to force the 403 response on looks like this mydomain.com/autodiscover/autodiscover.xml

I’ve tried modifying the default WordPress htaccess file by adding a line to ignore the custom directory but it doesn’t seem to work. When visiting the url I get a 404. I did create the directory and xml file and pushed them to our server.

Wondering if anyone has every run into this before and if they found a solution. My end goal would be to just force the 403 on the one file so my xml sitemaps don’t get blocked as well.

Thanks in advance.