Hello,
To get the best output we reccomend you to use the conversion plugin based on LibreOffice:
https://www.phpdocx.com/documentation/conversion-plugin/conversion-plugin-installation-and-set-up
Please install the latest version of LibreOffice.
If you prefer to use the conversion plugin based on OpenOffice as you are doing now, you may need to install some missing libraries in your OS. The error you get is related to a missing library (error while loading shared libraries: libtiff.so.3), you need to install it using yum. As this version of libtiff may not be available in your OS, you can install the version available and then create a symbolic link.
There's quick guide about common problems and how to debug the conversion plugin on:
https://www.phpdocx.com/documentation/conversion-plugin/common-problems-and-possible-errors
https://www.phpdocx.com/documentation/conversion-plugin/debugging-openoffice
https://www.phpdocx.com/documentation/conversion-plugin/debugging-libreoffice
Regards.