>”Amazon don't accept an existing photo of primary ID for their preferred ID verification check, it must be a photo taken by a camera on-device, and I don't have a webcam on my desktop PC”
In my experience, it was not possible to complete the verification via computer, even with a webcam. The verification site assumes and seems to require that you use a cellphone.
Now I'm glad I didn't have a webcam. It would have just added a few more steps to my tale of woe ;-)