version `SAMBA_UTIL_0.0.1' not found on Kubuntu 20.10
Yes, my suspicions were correct, the Groovy archives contain a new version that do not have some files but are required. Installing the latest from the Focal archives, then updating fixed the issue.
Here is the command I ran
sudo apt install libsmbclient=2:4.11.6+dfsg-0ubuntu1.6 libsmbios-c2=2.4.3-1 python3-samba=2:4.11.6+dfsg-0ubuntu1.6 samba-common-bin=2:4.11.6+dfsg-0ubuntu1.6 samba-common=2:4.11.6+dfsg-0ubuntu1.6 samba-dsdb-modules=2:4.11.6+dfsg-0ubuntu1.6 samba-libs=2:4.11.6+dfsg-0ubuntu1.6 samba-vfs-modules=2:4.11.6+dfsg-0ubuntu1.6 samba=2:4.11.6+dfsg-0ubuntu1.6 smbclient=2:4.11.6+dfsg-0ubuntu1.6 libwbclient0=2:4.11.6+dfsg-0ubuntu1.6 libldb2=2:2.0.10-0ubuntu0.20.04.2 python3-ldb=2:2.0.10-0ubuntu0.20.04.2
Then run sudo apt upgrade -y
to upgrade everything.