So it looks like you have been using this method?
ORACLE-BASE - OS Authentication
Have you seen forum threads like this?
Windows Authentication for Oracle — oracle-tech
I suppose for now I’d probably be looking for a command line interface to the db or some other app to connect to the oracle db from the workstation to eliminate any firewall problems or maybe be going through any oracle logging to see where the connection is failing.
Maybe this is of use?
Connect to the Oracle Database Using Windows Authentication - BizTalk Server | Microsoft Learn
TLDR I’d find a non clarion way to connect to the oracle db from the workstation, once that can be done, then trying the clarion app, or maybe even switch on the driver trace in clarion and see what appears there.