If I understand correctly:

1) That (Denon Kaseikyo) documentation is missing most Z1 and Z3 commands because those commands are available via the Sharp protocol.

2) It has lots of extra Z2 commands because those commands don't work in Z3 and Z4. I assume that means the Z1 versions of those extra commands use Sharp protocol.

It would be interesting to test whether the undocumented Kaseikyo commands, whose functions would duplicate Sharp commands, work.