Your source code contains fragments like below:
<tr id="match-1" class="match closed"<br />
title=”wedstrijd 1″>
Did you change the template for this table (via a hook) or have some sort of plugin installed that changes the HTML output?
In case of the latter, you can try to set the priority of my content filter higher by adding this line in your wp-config.php. And play a little with the number. The higher the number the later my filter will be executed.
define( 'FOOTBALL_POOL_CONTENT_FILTER_PRIORITY', 50 );