Hans, you really helped to get my gears turning. Oracle by default does not insert from a function, but there is a parameter we can add "PRAGMA AUTONOMOUS_TRANSACTION;" that will enable an Oracle function to perform an insert. I would not call this a "solution", as writing data back to a database is a basic function for any enterprise application, but will get us going for the time being.
I will modify the Function listed in your link to one that works for Oracle databases:
CREATE OR REPLACE FUNCTION writeback (i_writeback_message IN VARCHAR2)
INSERT INTO xtmp_writeback_table (FIELD1) VALUES (i_writeback_message);