Defender preventing data load from outside source

This church site loads its events from The City via a plugin. The htaccess file that Defender puts in is preventing the load of the data. I would rather allow the traffic from that site via htaccess and keep the security.
Is there a way to write it to prevent this error?

403 Permission Denied
You do not have permission for this request /wp-content/plugins/the-city-plaza/load_data.php?subdomain_key=northway&plaza_display=events&items_to_display=6&show_dates=on&show_type=0