Compatible Parameter in ODA 18.3 Databases

We've been trying for well over a year to make our development team understand the importance of getting our 11.2.0.4 and 12.1.0.2 based applications off compatible = 11.2.0.3 to no avail so far.  Now we're testing upgrading our ODAs from 12.1.2.12 to 18.3 but have been unable to create a new 11g database at anything under compatible = 11.2.0.4 or a new 12c database at anything under compatible = 12.1.0.2.  There used to be a template file that we could manipulate with a custom compatible setting to use when creating a new database but, if such an animal exists on