This wiki is written in the [[https://www.dokuwiki.org/wikitext|docuWiki syntax]], which is close to but different from mediaWiki (used by Wikipedia and others).
Thanks to a little googling, I found:
  * [[https://www.mediawiki.org/wiki/Topic:Rmw5y4misvc7lqqu|Migration from Dokuwiki]]
  * [[https://github.com/tstaerk/mediasyntax/blob/master/tools/dokuwiki2mediawiki..php]]
  * [[https://www.dokuwiki.org/tips:mediawiki_to_dokuwiki_converter|MediaWiki to DokuWiki Converter]] - The wrong way for me.

====== Sample Steps ======
<code bash>
mkdir dokuwiki2mediawiki
cd dokuwiki2mediawiki

#Get script (raw format from github)
wget https://raw.githubusercontent.com/tstaerk/mediasyntax/master/tools/dokuwiki2mediawiki.php

#Test, and see arguments
php dokuwiki2mediawiki.php

# copy original file to this location
cp /path/to/docuwiki/data/pages/subdir/page_i_want.txt .

# Convert file
php dokuwiki2mediawiki.php page_i_want.txt

#Convert all
find -type f -name '*.txt' -exec php dokuwiki2mediawiki.php {} \;

# View new markup
vi page_i_want.txt.mod

# Email new markup file to myself
echo "see attached" | mutt -a page_i_want.txt.mod -s "Email Subject" -- email_address@example.com
</code>