Call someone based on a High priority ticket

When a system down / high priority ticket comes in outside of normal working hours (A set conditions set are met).

We would like a team member to get a phone call to alert them that a system is down and a client has raised a ticket.

From talking with the Zendesk support team, a text can be triggered based on actions, but not a phone call. We can't see a third party app that can do this via Zendesk.

Any suggestions or could this be added for future release consideration, please?