i am having a problem that sounds very similar.
i mostly don't use z-wave a lot "interactively" - the majority of my z-wave devices currently are things like thermostats, sensors plus door locks.
recently, i got some z-wave modules on amazon because a) they were cheap b) they said they were "700 series" z-wave. i wanted to build-out more a more robust and reliable connection to some devices i need to be reliable (door locks). these were "minoston" brand. i was paying more attention than normal to indigo and z-wave and trying to get these devices to sync and i observed that most attempts to communicate with these devices (e.g. by sending a series of on/off commands over a short span) would seemingly cause z-wave to go through a repeatable sequence: lock up and stop responding. all z-wave commands (including to/from other devices stop working for a few seconds), then z-wave interface shuts down and fires a trigger i have setup to warn of "interface connection failure". z-wave connect re-establishes itself and comes back.
at first, i thought this was something unique/specific to these new modules. then i did a bit more testing and it seemed like i could reproduce the same set of symptoms by just sending on/off commands to some of my other z-wave devices. at that point, i started to think possibly this could be a symptom of one or more of a) recent migration to OS 12.3 then 12.4. b) recent migration from old mac hardware to newer mac hardware a few months ago. c) recent migration to Indigo version 2022.1. i also briefly entertained other ideas like that my z-stick was going bad.
if it is useful, i can send logs from multiple iterations through lockup / restart process but honestly from a glance, there's didn't seem to be much interesting detail there. the good news is i think i have a fairly reproducible test case with my current system. let me know if there's something i can do or test to help shed light on this.