My account got this too, fucking infuriating. The email method didn't work for me either. I was one click away from rage deleting my entire google account without setting up and transferring control elsewhere, so fed up with literally everything year after year.

Anyway, I discovered the "take a selfie" method was run by an incompetent or lazy third party service which I fooled with a random, AI-generated face pic found on image search. It would only accept input from a camera, so I logged in on my phone's browser, then kept that face pic I found fullscreened on my desktop monitor while angling the phone's front camera to make a detectable match (a ring around the selfie area would turn green). Was awkward and took a few tries but it worked and restored full account access without further harassment.