Can you open another browser tab and open the live log? Then when you do an exclude, you should see in the log if the exclude is actually running and successfully excludes the device. To me, it doesn't sound like the exclude is being done 100%. Hope this helps at least a little bit!
Issue resolved and switch now included on my Hubitat.
I think flipping the breaker for the circuit somehow reset the switch hardware in a way that the factory reset procedure wasn't.
The device had not been paired with my VeraPlus. I tried pairing/including it with the VeraPlus with no luck. So I then flipped the circuit breaker, and was then able to pair it with the VeraPlus. I then unpaired/excluded it from the VeraPlus, and was able to then include it again on the Hubitat.
Thanks, chevyman142000. Your hints helped convince me I wasn't missing anything obvious with the Zwave switch, and that I had to get more creative.
Now, to figure out why a Zigbee plug-in dimmer won't initialize with the Hubitat. Hmmm....
Yeah, had pulled the little air gap thingie several times, which I'd learned from this Iris video. It didn't seem to help. Maybe something was still stuck until I completely powered down the switch through the circuit breaker.
That said, with GE switches specifically, the airgap isn’t always enough to fully reboot the switch. So with this brand specifically, if you’re having trouble getting it to respond when it used to work just fine, trying turning off the current at the circuit breaker and then restoring it. That’s often enough to solve the last connection problem.