How to remove down/decommissioned Runbook Server in System Center Orchestrator 2022?

Hi all -

I tried to decommission a Runbook Server (1 of 6 we have). When I used the Deployment Manager, the only fitting option was "Uninstall", but this returned "RPC Unavailable" error, and couldn't do it. The RPC Service was running on both machines, there's no windows firewall enabled, and the two servers are on the same subnet.

I manually uninstalled the Orchestrator software from the server, and powered down the server. But the items still show up as assignable runbook servers and show up in Deployment Manager. I reinstalled, and tried all the steps again - same thing, RPC Unavailable. I've since manually uninstalled the software, and shutdown the machine.

Copilot recommended that I run some SQL commands directly against the database, but these came from an article from 2012, and appear related to Runbooks and not the Runbook Servers.

How can I eliminate this unneeded / downed / unavailable server? Thanks!