Yes, I managed to fix it.
On the CentOS build the SELINUX security settings are preventing the .cache file from running under the right process context. Have a look below at what we did to fix it:
Hopefully this will help someone else out who is running CentOS.
You have to add the " chcon -t httpd_sys_rw_content_t devices_relationships.cache" httpd process to the SELinux Context then poof the page starts to work again.
The other option ( nuclear option ) is to totally disable SELinux on CentOS7.
Alex