How to securely pass ssh key?

Question

SSH

Good day! I am writing an ssh key regeneration script for our team. In case of compromise, loss, forgotten password, regular change, etc.
Those. somewhere on the server there will be a script that runs on various events for various users. The script will create a key and put a public key in puppet (puppet will distribute it, at the same time overwriting the old keys). The next question is how to securely transfer the key to the user? How to pass passphrase?

Answer 1

No way, the system is flawed from the very beginning, the user himself must generate the key and the passphrase and give you the public key, the meaning in general is in the keys to which someone other than the user has access. That is, the default key is compromised, and in the case of an attacker entering, it is impossible to say for sure that the user leaked the key.

Answer 2

Are your team members unable to generate their own SSH key?