Either you want to be a customer or you won't.

Using a friend's paypal will get you banned for sure.

Why not just provide the passport if you want to use their service, jf that's their requirement.

It's an expensive document which is hard and slow to replace, and when Hetzner get hacked - and they like everyone will be, sooner or later - I would have to do that.

No problem for Hetzner, and it solves their authentication problem. Big problem for me.