NETDOM shows workstation, but wont remove it

In performing yearly maintenance, I ran NETDOM query and captured a list of workstations in my domain. This worked fine as always. Several workstations had either been removed last year due to upgrades and hardware failures. NETDOM lists them, but when I try to NETDOM remove I get an error message saying "Network path was not found.  The command failed to complete...".

I cannot ping the workstations

Neither DHCP nor DNS show the workstations. They only appear so far when I run netdom query.

The reason for this is I need to add an XPP workstation with a specific name (ABC123). Somewhere in the past, a workstation with that name had existed on the wire, but has been gone for - geez - a  LONG time. Again, neither DNS, DHCP, AD Computers, nothing shows this computer name, yet when I try to add it I get the error message saying a computer account with that name already exists in the domain. I ran netdom on the DC and see it listed, but I dont see it anywhere else. netdom shows it, but doesnt remove it....

is this a common issue?

ideas on how to remove these "ghost" computers?

Thanks!