I just gave it a try.
Background:
I fly on the 6th of DECEMBER! So a long time to go.
I'm from Germany, having a stopover in Abu Dhabi. I gave both flight numbers in the flight number section. But I put Germany as my origin of travel.
I uploaded Comirnaty vaccination certificate 1 and 2, and used the QR from 2 for both QR codes.
I DID NOT have a "real" booking confirmation that most of you have from your hotels. I just screenshotted my booking and bill from TUI travels (German documents). This document does also NOT include a RT-PCR test confirmation.
Insurance I had a special document from Ergo, screenshotted that, attached it.
Got my approval instantly, albeit in the Spam folder.