Ok, so basically, it says that if the condition of the device is suppressed, it should evaluate its resource health as 'down'.
Isn't this what you're expecting from the system? Or I did not understand correctly your request. Your CPE condition can be either 'critical' or 'suppressed' and both mean that the device is down.
You can try maybe to use ´contact status high sensitivity' that uses the contact status attribute.
You have Service 1: Device A. Service 2: Device B1, Service 3: Device B2.
Whenever Device A is unreachable, therefore both B1 and B2 are not reachable, alarm is generated on Service 1, Service 2 and Service 3.
Device A is reachable but device B1 is not reachable, device B2 is not reachable-> alarm on Service 2 and Service 3.
Device A is reachable, Device B1 is reachable, Device B2 is unreachable -> alarm on Service 3.
And to quote your request "
- If device A is reachable but B1 is unreachable (and therefore also B2 isn’t reachable): alarm will be only generated on Device B1"
I don't understand why device B2 is unreachable, as a result of B1 being unreachable. Aren't them both device B1 and device B2 connected to the same device A?