[Samba] How to fully remove entries to dead windows server

[Peter Pollock]

To save the whole back story, I borked everything and had to restore from
backups.

DC1 and DC2 (Samba DC's) came back fine

DC3 (Windows 2008 DC) did not come back. Which is fine, I wanted to
decommission it anyway.

I have seized all the FSMO roles (because DC3 previously held them all) and
replication SEEMS to be OK (users created on each machine replicate across
instantly, although showrepl throws up some odd errors on DC1 (below)).

My question though is what steps should I take to ensure that I completely
remove all entries to the dead windows server? I wasn't able to demote it
before it died and I don't want loose ends causing niggly problems in the
future.

Many thanks, Peter

P.S. Why does it say it failed replication, while also saying the last
success was exactly the same time as the last failure?

CN=Schema,CN=Configuration,DC=my,DC=domain
        Default-First-Site-Name\DC2 via RPC
                DSA object GUID: d0ab7757-99e0-4104-a22d-60e4b318e1b4
                Last attempt @ Thu Jul 16 00:35:58 2020 PDT failed, result
8453 (WERR_DS_DRA_ACCESS_DENIED)
                249708 consecutive failure(s).
                Last success @ Thu Jul 16 00:35:58 2020 PDT