Easiest way to do that (if you are absolutely sure that one service failing results in all others failing plus the SUM_OF_SERVICE fail), is to disable notifications for all those 5 services and create a new service called SUM_OF_SERVICE (which you can add to Nagios server host, because all of these services are on different servers, as you've said) which would have notifications enabled.
With that done, enable event_handlers for those 5 services and use submit_check_result to the SUM_OF_SERVICE service with the message "All 5 services are Critical" and exit with the critical exit code (2). For that be sure to disable (value 0) is_volatile variable in SUM_OF_SERVICE service definition cause you don't wan't to get same 5 messages for the service.
event_handler submit_check_result!Nagios_server!SUM_OF_SERVICE!2!"All 5 services are Critical"
The last configuration should be applied to all of other services (Pmon, WEB, LDAP, LOGIN).
I haven't tested this, I have written this as an idea from my head. So test this, and see if it works
I hope I understood well what you want. There are other ways to accomplish this, for example you could write a script that would check all those 5 services and return Critical exi code if any of them fails. If you know how to write scripts or some sort of programming, you could try to do that, and assign that script to be the check_command for SUM_OF SERVICE.