> The code is being shown to selected individuals deemed suitable and then they're telling me by way of proxy.
That is incorrect! The binaries are public and inspectable by anyone. The tools for doing it are bundled right into macOS -- like literally on every consumer's machine.[1]
Furthermore the protocol for connecting to a PCC node involves cryptographic proof that it's running a published binary.
[1] https://security.apple.com/documentation/private-cloud-compu...