FYI I just went through this. I had a Zen34 remote switch that I sent to Zooz for a warranty repair. There was no way to do a proper remove.
I just got the switch back and re-paired it. The old switch location was still there as a ghost node. I could not get the hub to remove it.
In my case, no matter how many times I clicked discover or refresh it would not give me a remove button. It would say the device was not responding but I could not remove it because there was no option to remove it.
I finally broke out the Z-Stick and I got rid of it. I flailed around a bit since I had not done that in quite some time, Once I got it set up though, it did remove the ghost node.
This thread helped me get everything set back up again.
