REQUEST_URI not matching explicit path and filename

Question

Really stumped, because form and syntax seem fine.

RewriteCond for REQUEST_URI is not matching the explicit path and filename. When isolated, RewriteCond for REQUEST_FI

Answer 1

I was unable to determine why server configuration or site code was forcing '410 Gone' response directive in htaccess to be overridden with a 404 response, so had to do something like this to tell googlebot to stop hunting for CSS/JS files that get purged periodically (and renamed when regenerated).

in .htaccess:

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule v_(.*)_(.*)$ /410response.php [L]

in 410response.php placed in root:

UPDATE I

The 404 response when attempting to use htaccess for the 410 directive was being forced by the server, because of server apparently having a custom 410 document, that apparently routed to 404. Adding a directive to prevent that then properly allowed use of htaccess to return 410 for pattern matches in RewriteRule. (I thought that I had already checked yesterday to see if this would work, since @MrWhite said in his answer above to control for server possibly having a custom 410; today when making this check, it did work and indicate that server 410-to-404 redirection was overridding my 410 directive.)

ErrorDocument 410 default
RewriteRule test\.txt$ - [NC,R=410]

MrWhite! I located this solution in one of your posts on Stack Exchange.