you will need to create an exteranl app under the virtual host and define PHPRC=/path/to/user/php.ini in that external application Environment and set php handler suffix mapping to this newly created external app. Let me know if it is not clear.
Did you set "script hander" to use the newly created external app? can you past your screenshot of your virtual host external app you just created, and script handler setting here? currrently we don't have a document for OLS yet, we will add it later.
I am sure that there is something wrong with the script handler and you are not advising. I deleted the php.ini and htaccess file completely but the error is still there. Please be more helpful, as it is totally your mistake the lack of documentation.