Third Party Credentials not accessible by any developer (including administrators)

Hi, 

We have to retrieve the third party credentials from an external repository but the client doesn't want developers (not even administrators) to have access to these credentials. 

We know that credentials in the connected systems are masked:

And we also know that values can be masked in Third Party Credentials (but this has to be done manually by an administrator): 

Does anyone know if this can be done dynamically or if there is a way for developers to not have access to these credentials?

Thanks!