Do you have a link to a video of the presentation?
It was essentially "here's how to use React to build a cockpit plugin from the ground up -- it's easy"
I'm a Python/Go backend developer, mostly, but Cockpit is easy enough that even I can write plugins for it. The workshop basically walked through the git tags in https://github.com/evol262/cockpit-boilerplate
cockpit-ovirt has a "Hosted Engine" tab which is an otopi parser. You'd find it to present exactly the same questions/options as "hosted-engine --deploy" in 4.0/4.1, with ansible and otopi deployments and a new UX in 4.2 which isn't a 1:1 representation of the questions asked.
Once Hosted Engine is deployed, the oVirt cockpit plugin can show the complete status of the HE cluster, put nodes into local maintenance, the whole cluster into maintenance, etc.