Ok, so I'll return to my previous reply:
Note from your access logs, "Apache/2.4.6 (CentOS) PHP/5.4.16"
Are your access logs now reporting PHP 7?
Additionally, see where the 200 is? 200 means success. Look for a 500 in that column, note the date and time, then look for an entry in your error log at that *exact* same date and time.