It's still available if you select any crypto currency in the form:

https://i.imgur.com/WOw0xal.png
https://i.imgur.com/aURKcKg.png
https://i.imgur.com/2yu2puh.png

It's pretty obvious to me that they don't have access to the code, so blocking German IPs was the only option they had. Meaning that if you are a German (currently) located in another country or just using a simple browser built-in VPN (e.g. in Opera) like I did, you can still register. It's really working, I just tried. I even filled the address data with a real German email domain and a real existing German address:

https://i.imgur.com/99KkUbH.png
https://i.imgur.com/a540feA.png

It even says "Account status: Verified:" although the chosen name, email address, DOB and phone number is completely fake 

What a shady book.