Well, I did some more searching and found that the Z2 uses the NEC1 protocol, device 51 so I gave that a try and it worked on my Z5. I found a lot of discrete codes, including the inputs I was looking for. There are also a bunch that are a bit scary - many brought up various service menus, one did a factory reset, and one actually did some sort of eeprom initialization (yikes!). Luckily I hit that one right after doing a factory reset so it didn't seem to save any bad settings. Just goes to show that playing around with these things can be dangerous (I knew full well the risks before starting).

Anyway, I stopped testing codes once I got into the 180s because one after another kept opening some sort of service menu so I didn't want to take any more chances. I had already found the codes I was looking for so I figured it was best to stop.

Here's the list of what I found for others who might be interested. Note that I skipped over 160-162 because I figured those are almost definitely the discrete power codes, just like the Z2:

160 - power on
161 - compulsory power off
162 - power off

I didn't want to test those because I don't really need them and I don't like cycling the power on my projector unnecessarily because of the stress on the lamp. Here's the list of codes I did find before stopping at 182:

0 power toggle
12 brightness toggle
13 user image 1
14 brilliant cinema
22 info
24 lamp control
28 menu
48 brightness
49 contrast
50 colour
51 lens iris
55 hdmi toggle
56 computer
61 video
62 s-video
67 freeze
130 screen
131 component toggle
137 exclamation bottom left corner
139 no show
140 cursor up
141 cursor down
144 hdmi1
146 factory reset
148 hdmi2
151 video
152 s-video
153 computer
156 service mode
157 eeprom initialization
163 service mode
164 brilliant cinema
165 component1
166 component2
167 lens cover demo
169 freeze on
170 freeze off
173 no show on
174 no show off
175 service mode
176 service mode
177 service mode
178 service mode
179 service mode
180 service mode
181 service mode
182 service mode