samba - May 2023 - How to cleanly remove a DC from Samba domain?

Hello,

I have a domain with three controllers (DC1/DC2/DC3). One is completely
non-existent and offline (DC3).

I am trying to remove the online controller completely from the domain. The
Samba wiki is currently offline, but from recollection I did the following to
remove DC2:

- transferred all FSMO to DC1
- demoted DC2

The demotion part seems to have succeeded:

---
root at dc2 ~# samba-tool domain demote -Uadministrator
Using dc1.ad.home.lan as partner server for the demotion
Password for [HOME\administrator]:
Deactivating inbound replication
Asking partner server dc1.ad.home.lan to synchronize from us
Changing userControl and container
Removing Sysvol reference: CN=DC2,CN=Enterprise,CN=Microsoft System
Volumes,CN=System,CN=Configuration,DC=ad,DC=home,DC=lan

... (prune lines for ldap updates)

Demote successful
---

Now if on DC1 I run "samba-tool drs showrepl" it only shows only DC3
(the offline one) but DC2 is no longer a replication partner...

However, DC2 is still a member computer (not domain controller) and I can't
seem to remove it:

---
root at dc1 ~# samba-tool computer list
DC1$
DC3$
... other computers
DC2$


root at dc1 ~# samba-tool computer delete DC2
ERROR(ldb): Failed to remove computer "DC2$" - subtree_delete: Unable
to delete a non-leaf node (it has 1 children)!
---

1) How do I go about removing it completely?
2) DC2 is still up and running Samba, can I stop it and bring it offline at this
stage? Also, would the demotion have worked if DC2 had samba daemons stopped or
are they required for the demotion part?

Thank you

I connected to LDAP via Apache Directory Studio and it seems that the child node
under the computer account is an RID set:

????????CN=RID Set,CN=DC2,CN=Computers,DC=ad,DC=home,DC=lan

Is this an omission of the demotion process? Should this havfe been removed? Is
it safe for me to delete this and try the "sambal-tool computer delete
DC2" again?