What do you mean cryptographically secure? Do you mean secure against Google or AWS attacking you by poisoning or recording the randomness? That type of securit

What do you mean cryptographically secure? Do you mean secure against Google or AWS attacking you by poisoning or recording the randomness? That type of security doesn't sound possible to me. There is the field of homomorphic encryption that has the goal of protecting you against attacks by your cloud provider, but from what I've heard it's extremely slow and requires to you rearchitect all your jobs.