Cracked with guid

[Mitch]

I tested more than 5 cd-keys (google, keygens), all they showed 8 digits pb guid (pb_plist).

Try this:
Join with one of those keys and save the pb guid and now reconnect. Also save this pb guid.
With key that isn't in use the guid should be the same.
In this case, you should be getting 2 different pb guids.