Hello,
Tidy is a PHP extension (https://www.php.net/manual/en/book.tidy.php) used by phpdocx to fix wrong HTML, handle CSS styles correctly and other tasks when importing HTML. It works in the same way with all HTML contents and CSS styles, so if you only have issues enabling forceNotTidy with list tags, maybe you are using not supported contents or styles or you are doing an type inline replacement instead a block type replacement (https://www.phpdocx.com/api-documentation/templates/replace-variable-html-Word-document). On the HTML API documentation you can read all HTML tags and CSS styles supported and samples.
In any case, enabling PHP Tidy is highly recommended.
About your question, please note that it's not a phpdocx issue but a PHP one and the solution depends on how you have installed PHP. Please check the following link: https://community.apachefriends.org/f/viewtopic.php?p=112503, maybe you can disable that setting in the PHP configuration or change its path to the correct one. If you are using a Windows server you can't use a UNIX path to point files.
Regards.