Losing signing keys for custom Guix channel

[elaexuotee@wilsonb.com]

Hey devs,

So I lost the PGP key that I was using to sign commits on a private Guix
channel of mine. Is there a way to introduce a hard break in my channel
authentication?

Despite updating authorization settings, pulls complain that my latest commit
isn't signed by an authorized key.

Here are the changes I've made:
- New public key added to keyring branch
- Appended new key fingerprint to .guix-authorizations (at commit X)
- Update introduction in .config/guix/channels.scm
  - Point to commit X
  - Update openpgp-fingerprint

As a sanity check, I've confirmed that the fingerprint on commit X, the
fingerprint in .guix-authorizations, and the openpgp-fingerprint in my
channels.scm are all the same.

What am I missing?