Only thing I can think of is that its too far gone and unable to function with all the garbage in there.
Be all end all detailed instructions: How To: Remove Ghosts using hub tools or a UZB Stick
Yes it works to remove nodes, 100% (although if you cannot even pair the stick it wont work).
Official Docs: How to Build a Solid Z-Wave Mesh | Hubitat Documentation
There is another thread as well but I having a hard time finding it.