first we have to be clear on what we are talking about.
The 'default' template is the old template and resides in lib/tpl/default
The new 'dokuwiki' template resided in lib/tpl/dokuwiki
Be sure you have your settings right and put the code in the main.php of the right map.
secondly I'm not sure where you want the link on your page.
the codes set as an example in
https://www.dokuwiki.org/plugin:dw2pdf work for me very well.
So please lets us know more and we probably can help you.