I don't know how many members there are in your management that want notifications but you could make them watchers once an agent determines the true severity. This would be a manual process but it gets the job done.
You could also make a work around using approvals but it would look kind of funny and still require a manual step. Build an approval board with members of management that want notifications and then each time a ticket is determined to be Critical, the agent can request approval from the "Critical Board" and they all get notices. They can choose to vote on critical status or just approve that they saw it.