The answer is a "simple" trigger as I've outlined below for you. I didn't have enough information to name it properly, but hopefully you will be able to fill in the gaps. This will fire AFTER the insert operation on the SQL side, then insert the relevant records to the Oracle linked server (assuming it's setup correctly).
However, a few words of ...
If you check the How to Create a Linked Server doc, you'll understand that your current configuration works like this:
Be made using the login's current security context Specify that a connection will be made using the current security context of the
login for logins not defined in the list. If connected to the local
server using Windows Authentication, ...
One thing you could try is to create stored procedure that would select from a View
When creating stored procedure, use EXECUTE AS clause and set it to a Windows-authenticated account (grant all necessary permissions to this account, required to read from I:\Folder)
Grant execute on procedure to SBA_USER
This way when SBA_USER executes procedure, procedure ...
You'll find the linked servers login mappings in sys.linked_logins view.
This, in turn accesses the master.sys.syslnklgns table (in case this gives something useful), but you can only access the real systems tables when you connect using the Dedicated Admin Connection (/A with sqlcmd.exe).