Tell me if I am thinking about this correctly.
If you received a pardon for a specific crime, you couldn't take the 5th on questions related to that crime. I think that's what Paul was talking about referencing some court ruling. Note: I am not sure I agree with that ruling. I don't think we should be compelled to speak, ever. The freedom to remain silent is a core individual liberty, IMO.
But the argument seems to be that because Fauci received and accepted a pardon for any crimes he may have committed from 2014 to 2025, he should be compelled to testify on anything that happened over that decade+, since there is no jeopardy protected by the 5th. I think I get the logic, but don't agree with it.
Also, you seem to imply that a person may have to justify their use of the 5th, I don't get that at all.