@smeagol recap, you should have power looking at your connections.
That black plug next to the fuse is where the power comes in. Even if nothing else worked, that should be giving you power. I know it isn't easy, but you need to find a way to verify that harness is getting power. Maybe on those jumpers you installed if you disconnect them and test the yellow and black they should be getting battery power. if there is no power there you're problem is at the other end of that main harness. It's big and awkward, and if not seated, that could be why the unit isn't getting power.
The white capped factory wire you didn't find a destination for, I do not believe it gets connected (see grey wire below).
The canbus with SH 20231020, I think that is the one for the camera. I never got that connected right, but it wouldn't effect the radio not powering on.
The canbus with TZY is the one to control the unit. It looks like you have both of these connected correctly.
The green wires and other small harness are both correct.
Now, one plug that isn't correct, over by the connector with the two green wires, you should have another one of the provided harnesses there. It's the one with like 6 or more RCA's coming from it. That is where you should plug the audio wires from the amp jumper. Where you have them plugged is for an input signal. You need to plug them into just the FR/FL out RCAs on the harness you didn't connect. The rest of the RCAs don't get used.
All of the head units are slightly different, I think there were three different factory units. BUT there was one wire on the amp you should not have plugged back in. I think it was grey (attached the photo from the website).
Wish I could be more help. Your wiring is correct enough that you should have power. If you want to talk to them, just go to what'sapp. They take a day, minimum, to reply to emails.
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