Weinstein is the boss. So you'd never give him immunity to the case, he's the target.
If Weinstein had a close "ally", who was less important for justice but important to testify for the case... even if that "ally" had crimes associated with him, you'd want to give that "Hypothetical ally" immunity. _THEN_ you force the ally to talk (if the ally fails to talk in court, you throw him in jail for contempt of court, and take away their immunity).
