How about this:
Trigger alert when all of the following apply
Node status is equal to Down
Trigger alert when any of the following apply
Node Name is equal to Device01
Node Name is equal to Device02
Node Name is equal to Device03
Is that like a sub condition?
Yes, after you define the 1st line Node is equal to down (simple condition) >> add another line but select Add Condition Group and change it to ANY and define all 3 lines with Simple Condition.