I tried to get the domain owner from oracle and ArcCatalog using the same credentials.
I found the 3 domain owners from oracle sde (SELECT DISTINCT(owner) from sde.TABLE_REGISTRY )
I found the 1 domain owner from ArcCatalog.
I could see the difference in domain names between ArcCatlog & Oracle.
Could you please share the SQL query to retrieve the SDE domain name?
Try taking a look at this: https://desktop.arcgis.com/en/arcmap/10.5/manage-data/using-sql-with-gdbs/example-finding-domain-own...