So I don't know what file access logs I should look at. All the samba logs have essentially had nothing at all in them except for variations on [2023/09/28 23:50:31, 0] ../../source3/rpc_server/rpc_worker.c:1125(rpc_worker_main) rpcd_winreg version 4.18.6 started. Copyright Andrew Tridgell and the Samba Team 1992-2023
so it doesn't seem like they're going to be of any help here...
The new files do show and launch on the server itself just fine.
Stopping samba does produce the expected timeout errors on clients
Renamed file does show as renamed. Bonus, a new file I created on the server from context menu "New text file" entry does also show on clients