Unable to get GE 45601 Z-Wave to rejoin SmartThings Hub V1 Network

Continuing the discussion from System put me at risk:

Of course, I know that still, unfortunately, these old GE Remotes cannot be used in the same way as the Aeon Minimotes and so other types of Z-Wave controllers, but mine has served me well as a secondary for direct control of various Z-Wave lights around my home.

Unfortunately, I was messing around trying to add a CT-30 Thermostat to it, and somehow hit the “Reset” function.

Now I can’t get it to exclude and rejoin the network. Perhaps I’ve not tried hard enough or … Well, has something changed that makes this no longer possible / compatible? Thanks…