It seem to be clear that an "unmonitored host" only roll firewall and not willpower + firewall (there is an example of that on SR6 p. 178).
Less clear perhaps what "unmonitored" means in this case. I think different people might assume different things here.
- A host that does not have a spider on duty at all, host have been unattended for some time
- A host that typically have a spider on duty but the spider is currently not logged into the host
- A host that have a spider on duty and the spider is inside the host, but currently distracted from actively monitoring the host
