If the (or a?) goal is basically to get data from a suite of Kobo forms (aka XForms) submitted via KoboCollect (aka ODK Collect) into a Postgres database, you might actually want to take a quick look at ODK Central, which is an OpenRosa compatible (therefore should be compatible with both your existing forms and if you want to continue to use KoboCollect for data collection) Postgres DB backend. Central also provides a full REST API to all forms and submissions, and an optional GUI frontend if needed.
Disclaimer: I’m on the ODK TSC. But there has been some interest expressed in using Central to perhaps replace KoBoKat.
