Thread:Manual talk:Short URL/Apache/Cann't get this extension working/reply

is wrong, it must start with /.

Besides that it doesn't look like you have followed the guide at all.

The -f and -d don't apply when doing /wiki/$1 urls and mediawiki is in a separate folder and they're in the wrong spot.

And there is no mention anywhere of, which is likely intercepting any url belonging to your wiki and sending it somewhere else.