Greetings,
I've followed the instructions and created an rpool on a USB drive to boot Catalina from. I used a clean install of Catalina in a VM, and also used the updated Catalina package from 2019-10-21. Attached is a photo of the error I'm getting on boot.
After getting the error, to be absolutely sure the updated files in the package from the 21st were on the rpool, I extracted the package contents with Pacifist onto the pool.
Any ideas where to go from here?