This might be worth a try.
Make sure that your are *at least* logging php errors in a specific file. The line you are looking for is in php.ini, and may look something like
error_log = /tmp/php_error_log
This will create a file in the /tmp folder and any php errors will be logged there.
This caught me out when I rebuilt my server, since php’s default setting is to *not* output errors to the browser.
HTH, but if not, good luck. ??