Jibe has different forms, but essentially, it's software that's supposed to be run on your carrier's network. As a customer, it doesn't matter if your carrier is using the network-hosted version of Jibe or the cloud version, it's your carrier's responsibility to Make It Work.

For things like SMS/MMS servers, SIP servers, and other carrier infrastructure, carriers still like to run this stuff themselves. For RCS this was also the case a decade ago, but then RCS died an unceremonious death when third party messengers ate its lunch and carriers failed spectacularly trying to advertise "joyn".

Jibe is a black box that must follow the RCS specification. It's your carrier's responsibility to make that work. As long as Apple is following the RCS spec, they're right in saying it's not their problem. Your carrier should be telling Google to fix their shit.