Delete the IG automatic row processing and create a custom PL/SQL code processing something like below:

Declare 
   Cursor c_ig_view
     is
   Select empno, ename, salary
      from emp_view;
      /* add where condition if added for the IG */
Begin
    for c in c_ig_view loop
       /* Insert into the table */
       insert into emp_table (empno, ename, salary)
         values (c.empno, c.ename, c.salary);
    end loop;
End;

In the above code, change the cursor query to the same as your interactive grid query.

Your interactive grid is based on the view and not editable, so you can use the query in cursor you used for the interactive grid.

Also, the Save button in the interactive grid will not work this.

Create another button and set the action type to Submit and on submit the above process will execute. But make sure that the above process should be written above the close dialog process if exists.

Let me know if any further questions.