I paired mine without security and have since then toyed with a custom driver as well (ported from ST). I plan on eventually testing it again with the S2 to see if I can get it working correctly using my driver (this will rule out if the stock driver is the issue or something with the device or the C7 radio).
Anyway, per Zooz I have the defaults changed on my custom driver and it has been working like this for months without issues. Granted I only have a phone charger plugged into it but it does log the events as expected and has not caused any problems.
If anyone is interested in trying out this driver I have it on a separate branch on my github for now until it is done and I merge it with main: Hubitat/Drivers/zooz-plugs at double-plug · jtp10181/Hubitat · GitHub
