Hubitat ended up adding support for the USB reporting to their built-in handler and I think it also supports all the settings in the latest firmware so you're correct, there's no reason to use this handler. (I forgot I wrote a custom Hubitat handler and responded from my phone thinking this was the ST forum)
That being said, unless the handler was increasing the number of reports sent to or from the device, which this one doesn't, there's no way the handler could be causing your z-wave issues.
The more reports it sends, the more z-wave issues it will cause, so set the frequency reporting to the highest setting for all the measurements you're not doing anything with. You should do this for all your metering z-wave devices...
