i am not sure myself 
i haven’t worked with more complex tagged arrays for quite some time (am not ConfD developer, just sort of more extensive (in some areas) user).
my unverified assumption is that:
-
it should be possible to send specific case items as part of get_object() response data
-
you will probably still need to have get_case() implementation in case confd internally needs / invokes it for some processing
(second point possibly contradicts with my previous statement about confd implying which case is set, but maybe it’s only for some/specific cases)
Unless someone else can confirm/add more info, please test try it, as i assume you have the the above work-in-progress and can verify it more quickly…
edit:
assuming my first point above is true, tagged array rules about nested lists/containers/etc. still apply, so if the nested items of choice you have are also “nests” - containers/lists, you can not add all the sub-nested children, only the nest itself - resp. its stub as described/explained in other forum topics/man pages) and there will be subsequent nested calls…