Oh! Sorry, you described the current state of things so well I assumed you were close to the project.
Here is the github repo where banking app compatibilities are tracked: https://github.com/PrivSec-dev/banking-apps-compat-report
And it's rendered to a page here: https://privsec.dev/posts/android/banking-applications-compa...
Hah - both were in my browser history, yes I know them :) I misunderstood and thought you had sent direct emails to relevant parties arguing for why they should be allowed on grapheneos.
Thanks anyway!